GoogleSQL for BigQuery supports string functions. These string functions work on two different values: STRING and BYTES data types. STRING values must be well-formed UTF-8.
Functions that return position values, such as STRPOS, encode those positions as INT64. The value 1 refers to the first character (or byte), 2 refers to the second, and so on. The value 0 indicates an invalid position. When working on STRING types, the returned positions refer to character positions.
All string comparisons are done byte-by-byte, without regard to Unicode canonical equivalence.
Function list
| Name | Summary |
|---|---|
ARRAY_TO_STRING | Produces a concatenation of the elements in an array as a STRING value. For more information, see Array functions. |
ASCII | Gets the ASCII code for the first character or byte in a STRING or BYTES value. |
BYTE_LENGTH | Gets the number of BYTES in a STRING or BYTES value. |
CHAR_LENGTH | Gets the number of characters in a STRING value. |
CHARACTER_LENGTH | Synonym for CHAR_LENGTH. |
CHR | Converts a Unicode code point to a character. |
CODE_POINTS_TO_BYTES | Converts an array of extended ASCII code points to a BYTES value. |
CODE_POINTS_TO_STRING | Converts an array of extended ASCII code points to a STRING value. |
COLLATE | Combines a STRING value and a collation specification into a collation specification-supported STRING value. |
CONCAT | Concatenates one or more STRING or BYTES values into a single result. |
CONTAINS_SUBSTR | Performs a normalized, case-insensitive search to see if a value exists as a substring in an expression. |
EDIT_DISTANCE | Computes the Levenshtein distance between two STRING or BYTES values. |
ENDS_WITH | Checks if a STRING or BYTES value is the suffix of another value. |
FORMAT | Formats data and produces the results as a STRING value. |
FROM_BASE32 | Converts a base32-encoded STRING value into a BYTES value. |
FROM_BASE64 | Converts a base64-encoded STRING value into a BYTES value. |
FROM_HEX | Converts a hexadecimal-encoded STRING value into a BYTES value. |
INITCAP | Formats a STRING as proper case, which means that the first character in each word is uppercase and all other characters are lowercase. |
INSTR | Finds the position of a subvalue inside another value, optionally starting the search at a given offset or occurrence. |
LAX_STRING | Attempts to convert a JSON value to a SQL STRING value. For more information, see JSON functions. |
LEFT | Gets the specified leftmost portion from a STRING or BYTES value. |
LENGTH | Gets the length of a STRING or BYTES value. |
LOWER | Formats alphabetic characters in a STRING value as lowercase. Formats ASCII characters in a BYTES value as lowercase. |
LPAD | Prepends a STRING or BYTES value with a pattern. |
LTRIM | Identical to the TRIM function, but only removes leading characters. |
NORMALIZE | Case-sensitively normalizes the characters in a STRING value. |
NORMALIZE_AND_CASEFOLD | Case-insensitively normalizes the characters in a STRING value. |
OCTET_LENGTH | Alias for BYTE_LENGTH. |
REGEXP_CONTAINS | Checks if a value is a partial match for a regular expression. |
REGEXP_EXTRACT | Produces a substring that matches a regular expression. |
REGEXP_EXTRACT_ALL | Produces an array of all substrings that match a regular expression. |
REGEXP_INSTR | Finds the position of a regular expression match in a value, optionally starting the search at a given offset or occurrence. |
REGEXP_REPLACE | Produces a STRING value where all substrings that match a regular expression are replaced with a specified value. |
REGEXP_SUBSTR | Synonym for REGEXP_EXTRACT. |
REPEAT | Produces a STRING or BYTES value that consists of an original value, repeated. |
REPLACE | Replaces all occurrences of a pattern with another pattern in a STRING or BYTES value. |
REVERSE | Reverses a STRING or BYTES value. |
RIGHT | Gets the specified rightmost portion from a STRING or BYTES value. |
RPAD | Appends a STRING or BYTES value with a pattern. |
RTRIM | Identical to the TRIM function, but only removes trailing characters. |
SAFE_CONVERT_BYTES_TO_STRING | Converts a BYTES value to a STRING value and replace any invalid UTF-8 characters with the Unicode replacement character, U+FFFD. |
SOUNDEX | Gets the Soundex codes for words in a STRING value. |
SPLIT | Splits a STRING or BYTES value, using a delimiter. |
STARTS_WITH | Checks if a STRING or BYTES value is a prefix of another value. |
STRING (JSON) | Converts a JSON string to a SQL STRING value. For more information, see JSON functions. |
STRING (Timestamp) | Converts a TIMESTAMP value to a STRING value. For more information, see Timestamp functions. |
STRING_AGG | Concatenates non-NULL STRING or BYTES values. For more information, see Aggregate functions. |
STRPOS | Finds the position of the first occurrence of a subvalue inside another value. |
SUBSTR | Gets a portion of a STRING or BYTES value. |
SUBSTRING | Alias for SUBSTR |
TO_BASE32 | Converts a BYTES value to a base32-encoded STRING value. |
TO_BASE64 | Converts a BYTES value to a base64-encoded STRING value. |
TO_CODE_POINTS | Converts a STRING or BYTES value into an array of extended ASCII code points. |
TO_HEX | Converts a BYTES value to a hexadecimal STRING value. |
TRANSLATE | Within a value, replaces each source character with the corresponding target character. |
TRIM | Removes the specified leading and trailing Unicode code points or bytes from a STRING or BYTES value. |
UNICODE | Gets the Unicode code point for the first character in a value. |
UPPER | Formats alphabetic characters in a STRING value as uppercase. Formats ASCII characters in a BYTES value as uppercase. |
ASCII
ASCII(value) Description
Returns the ASCII code for the first character or byte in value. Returns 0 if value is empty or the ASCII code is 0 for the first character or byte.
Return type
INT64
Examples
SELECT ASCII('abcd') as A, ASCII('a') as B, ASCII('') as C, ASCII(NULL) as D; /*-------+-------+-------+-------+ | A | B | C | D | +-------+-------+-------+-------+ | 97 | 97 | 0 | NULL | +-------+-------+-------+-------*/ BYTE_LENGTH
BYTE_LENGTH(value) Description
Gets the number of BYTES in a STRING or BYTES value, regardless of whether the value is a STRING or BYTES type.
Return type
INT64
Examples
SELECT BYTE_LENGTH('абвгд') AS string_example; /*----------------+ | string_example | +----------------+ | 10 | +----------------*/ SELECT BYTE_LENGTH(b'абвгд') AS bytes_example; /*----------------+ | bytes_example | +----------------+ | 10 | +----------------*/ CHAR_LENGTH
CHAR_LENGTH(value) Description
Gets the number of characters in a STRING value.
Return type
INT64
Examples
SELECT CHAR_LENGTH('абвгд') AS char_length; /*-------------+ | char_length | +-------------+ | 5 | +------------ */ CHARACTER_LENGTH
CHARACTER_LENGTH(value) Description
Synonym for CHAR_LENGTH.
Return type
INT64
Examples
SELECT 'абвгд' AS characters, CHARACTER_LENGTH('абвгд') AS char_length_example /*------------+---------------------+ | characters | char_length_example | +------------+---------------------+ | абвгд | 5 | +------------+---------------------*/ CHR
CHR(value) Description
Takes a Unicode code point and returns the character that matches the code point. Each valid code point should fall within the range of [0, 0xD7FF] and [0xE000, 0x10FFFF]. Returns an empty string if the code point is 0. If an invalid Unicode code point is specified, an error is returned.
To work with an array of Unicode code points, see CODE_POINTS_TO_STRING
Return type
STRING
Examples
SELECT CHR(65) AS A, CHR(255) AS B, CHR(513) AS C, CHR(1024) AS D; /*-------+-------+-------+-------+ | A | B | C | D | +-------+-------+-------+-------+ | A | ÿ | ȁ | Ѐ | +-------+-------+-------+-------*/ SELECT CHR(97) AS A, CHR(0xF9B5) AS B, CHR(0) AS C, CHR(NULL) AS D; /*-------+-------+-------+-------+ | A | B | C | D | +-------+-------+-------+-------+ | a | 例 | | NULL | +-------+-------+-------+-------*/ CODE_POINTS_TO_BYTES
CODE_POINTS_TO_BYTES(ascii_code_points) Description
Takes an array of extended ASCII code points as ARRAY<INT64> and returns BYTES.
To convert from BYTES to an array of code points, see TO_CODE_POINTS.
Return type
BYTES
Examples
The following is a basic example using CODE_POINTS_TO_BYTES.
SELECT CODE_POINTS_TO_BYTES([65, 98, 67, 100]) AS bytes; -- Note that the result of CODE_POINTS_TO_BYTES is of type BYTES, displayed as a base64-encoded string. -- In BYTES format, b'AbCd' is the result. /*----------+ | bytes | +----------+ | QWJDZA== | +----------*/ The following example uses a rotate-by-13 places (ROT13) algorithm to encode a string.
SELECT CODE_POINTS_TO_BYTES(ARRAY_AGG( (SELECT CASE WHEN chr BETWEEN b'a' and b'z' THEN TO_CODE_POINTS(b'a')[offset(0)] + MOD(code+13-TO_CODE_POINTS(b'a')[offset(0)],26) WHEN chr BETWEEN b'A' and b'Z' THEN TO_CODE_POINTS(b'A')[offset(0)] + MOD(code+13-TO_CODE_POINTS(b'A')[offset(0)],26) ELSE code END FROM (SELECT code, CODE_POINTS_TO_BYTES([code]) chr) ) ORDER BY OFFSET)) AS encoded_string FROM UNNEST(TO_CODE_POINTS(b'Test String!')) code WITH OFFSET; -- Note that the result of CODE_POINTS_TO_BYTES is of type BYTES, displayed as a base64-encoded string. -- In BYTES format, b'Grfg Fgevat!' is the result. /*------------------+ | encoded_string | +------------------+ | R3JmZyBGZ2V2YXQh | +------------------*/ CODE_POINTS_TO_STRING
CODE_POINTS_TO_STRING(unicode_code_points) Description
Takes an array of Unicode code points as ARRAY<INT64> and returns a STRING.
To convert from a string to an array of code points, see TO_CODE_POINTS.
Return type
STRING
Examples
The following are basic examples using CODE_POINTS_TO_STRING.
SELECT CODE_POINTS_TO_STRING([65, 255, 513, 1024]) AS string; /*--------+ | string | +--------+ | AÿȁЀ | +--------*/ SELECT CODE_POINTS_TO_STRING([97, 0, 0xF9B5]) AS string; /*--------+ | string | +--------+ | a例 | +--------*/ SELECT CODE_POINTS_TO_STRING([65, 255, NULL, 1024]) AS string; /*--------+ | string | +--------+ | NULL | +--------*/ The following example computes the frequency of letters in a set of words.
WITH Words AS ( SELECT word FROM UNNEST(['foo', 'bar', 'baz', 'giraffe', 'llama']) AS word ) SELECT CODE_POINTS_TO_STRING([code_point]) AS letter, COUNT(*) AS letter_count FROM Words, UNNEST(TO_CODE_POINTS(word)) AS code_point GROUP BY 1 ORDER BY 2 DESC; /*--------+--------------+ | letter | letter_count | +--------+--------------+ | a | 5 | | f | 3 | | r | 2 | | b | 2 | | l | 2 | | o | 2 | | g | 1 | | z | 1 | | e | 1 | | m | 1 | | i | 1 | +--------+--------------*/ COLLATE
COLLATE(value, collate_specification) Takes a STRING and a collation specification. Returns a STRING with a collation specification. If collate_specification is empty, returns a value with collation removed from the STRING.
The collation specification defines how the resulting STRING can be compared and sorted. To learn more, see Collation.
collation_specificationmust be a string literal, otherwise an error is thrown.- Returns
NULLifvalueisNULL.
Return type
STRING
Examples
In this example, the weight of a is less than the weight of Z. This is because the collate specification, und:ci assigns more weight to Z.
WITH Words AS ( SELECT COLLATE('a', 'und:ci') AS char1, COLLATE('Z', 'und:ci') AS char2 ) SELECT ( Words.char1 < Words.char2 ) AS a_less_than_Z FROM Words; /*----------------+ | a_less_than_Z | +----------------+ | TRUE | +----------------*/ In this example, the weight of a is greater than the weight of Z. This is because the default collate specification assigns more weight to a.
WITH Words AS ( SELECT 'a' AS char1, 'Z' AS char2 ) SELECT ( Words.char1 < Words.char2 ) AS a_less_than_Z FROM Words; /*----------------+ | a_less_than_Z | +----------------+ | FALSE | +----------------*/ CONCAT
CONCAT(value1[, ...]) Description
Concatenates one or more values into a single result. All values must be BYTES or data types that can be cast to STRING.
The function returns NULL if any input argument is NULL.
Return type
STRING or BYTES
Examples
SELECT CONCAT('T.P.', ' ', 'Bar') as author; /*---------------------+ | author | +---------------------+ | T.P. Bar | +---------------------*/ SELECT CONCAT('Summer', ' ', 1923) as release_date; /*---------------------+ | release_date | +---------------------+ | Summer 1923 | +---------------------*/ With Employees AS (SELECT 'John' AS first_name, 'Doe' AS last_name UNION ALL SELECT 'Jane' AS first_name, 'Smith' AS last_name UNION ALL SELECT 'Joe' AS first_name, 'Jackson' AS last_name) SELECT CONCAT(first_name, ' ', last_name) AS full_name FROM Employees; /*---------------------+ | full_name | +---------------------+ | John Doe | | Jane Smith | | Joe Jackson | +---------------------*/ CONTAINS_SUBSTR
CONTAINS_SUBSTR( expression, search_value_literal [, json_scope => json_scope_value ] ) Description
Performs a normalized, case-insensitive search to see if a value exists as a substring in an expression. Returns TRUE if the value exists, otherwise returns FALSE.
Before values are compared, they are normalized and case folded with NFKC normalization. Wildcard searches aren't supported.
Arguments
search_value_literal: The value to search for. It must be aSTRINGliteral or aSTRINGconstant expression.expression: The data to search over. The expression can be a column or table reference. A table reference is evaluated as aSTRUCTwhose fields are the columns of the table. A column reference is evaluated as one the following data types:STRINGINT64BOOLNUMERICBIGNUMERICTIMESTAMPTIMEDATEDATETIMEARRAYSTRUCT
When the expression is evaluated, the result is cast to a
STRING, and then the function looks for the search value in the result.You can perform a cross-field search on an expression that evaluates to a
STRUCTorARRAY. If the expression evaluates to aSTRUCT, the cross-field search is recursive and includes all subfields inside theSTRUCT.In a cross-field search, each field and subfield is individually converted to a string and searched for the value. The function returns
TRUEif at least one field includes the search value; otherwise, if at least one field isNULL, it returnsNULL; otherwise, if the search value isn't found and all fields are non-NULL, it returnsFALSE.If the expression is
NULL, the return value isNULL.json_scope: A named argument with aSTRINGvalue. Takes one of the following values to indicate the scope ofJSONdata to be searched. It has no effect ifexpressionisn'tJSONor doesn't contain aJSONfield.'JSON_VALUES': Only theJSONvalues are searched. Ifjson_scopeis not provided, this is used by default.'JSON_KEYS': Only theJSONkeys are searched.'JSON_KEYS_AND_VALUES': TheJSONkeys and values are searched.
Return type
BOOL
Examples
The following query returns TRUE because this case-insensitive match was found: blue house and Blue house.
SELECT CONTAINS_SUBSTR('the blue house', 'Blue house') AS result; /*--------+ | result | +--------+ | true | +--------*/ The following query returns TRUE similar to the above example, but in this case the search value is a constant expression with CONCAT function.
SELECT CONTAINS_SUBSTR('the blue house', CONCAT('Blue ', 'house')) AS result; /*--------+ | result | +--------+ | true | +--------*/ The following query returns FALSE because blue wasn't found in the red house.
SELECT CONTAINS_SUBSTR('the red house', 'blue') AS result; /*--------+ | result | +--------+ | false | +--------*/ The following query returns TRUE because Ⅸ and IX represent the same normalized value.
SELECT '\u2168 day' AS a, 'IX' AS b, CONTAINS_SUBSTR('\u2168', 'IX') AS result; /*----------------------+ | a | b | result | +----------------------+ | Ⅸ day | IX | true | +----------------------*/ The following query returns TRUE because 35 was found inside a STRUCT field.
SELECT CONTAINS_SUBSTR((23, 35, 41), '35') AS result; /*--------+ | result | +--------+ | true | +--------*/ The following query returns TRUE because jk was found during a recursive search inside a STRUCT.
SELECT CONTAINS_SUBSTR(('abc', ['def', 'ghi', 'jkl'], 'mno'), 'jk'); /*--------+ | result | +--------+ | true | +--------*/ The following query returns TRUE because NULLs are ignored when a match is found found inside a STRUCT or ARRAY.
SELECT CONTAINS_SUBSTR((23, NULL, 41), '41') AS result; /*--------+ | result | +--------+ | true | +--------*/ The following query returns NULL because a NULL existed in a STRUCT that didn't result in a match.
SELECT CONTAINS_SUBSTR((23, NULL, 41), '35') AS result; /*--------+ | result | +--------+ | null | +--------*/ In the following query, an error is thrown because the search value can't be a literal NULL.
SELECT CONTAINS_SUBSTR('hello', NULL) AS result; -- Throws an error The following examples reference a table called Recipes that you can emulate with a WITH clause like this:
WITH Recipes AS (SELECT 'Blueberry pancakes' as Breakfast, 'Egg salad sandwich' as Lunch, 'Potato dumplings' as Dinner UNION ALL SELECT 'Potato pancakes', 'Toasted cheese sandwich', 'Beef stroganoff' UNION ALL SELECT 'Ham scramble', 'Steak avocado salad', 'Tomato pasta' UNION ALL SELECT 'Avocado toast', 'Tomato soup', 'Blueberry salmon' UNION ALL SELECT 'Corned beef hash', 'Lentil potato soup', 'Glazed ham') SELECT * FROM Recipes; /*-------------------+-------------------------+------------------+ | Breakfast | Lunch | Dinner | +-------------------+-------------------------+------------------+ | Bluberry pancakes | Egg salad sandwich | Potato dumplings | | Potato pancakes | Toasted cheese sandwich | Beef stroganoff | | Ham scramble | Steak avocado salad | Tomato pasta | | Avocado toast | Tomato soup | Blueberry samon | | Corned beef hash | Lentil potato soup | Glazed ham | +-------------------+-------------------------+------------------*/ The following query searches across all columns of the Recipes table for the value toast and returns the rows that contain this value.
SELECT * FROM Recipes WHERE CONTAINS_SUBSTR(Recipes, 'toast'); /*-------------------+-------------------------+------------------+ | Breakfast | Lunch | Dinner | +-------------------+-------------------------+------------------+ | Potato pancakes | Toasted cheese sandwich | Beef stroganoff | | Avocado toast | Tomato soup | Blueberry samon | +-------------------+-------------------------+------------------*/ The following query searches the Lunch and Dinner columns of the Recipe table for the value potato and returns the row if either column contains this value.
SELECT * FROM Recipes WHERE CONTAINS_SUBSTR((Lunch, Dinner), 'potato'); /*-------------------+-------------------------+------------------+ | Breakfast | Lunch | Dinner | +-------------------+-------------------------+------------------+ | Bluberry pancakes | Egg salad sandwich | Potato dumplings | | Corned beef hash | Lentil potato soup | Glazed ham | +-------------------+-------------------------+------------------*/ The following query searches across all columns of the Recipes table except for the Lunch and Dinner columns. It returns the rows of any columns other than Lunch or Dinner that contain the value potato.
SELECT * FROM Recipes WHERE CONTAINS_SUBSTR( (SELECT AS STRUCT Recipes.* EXCEPT (Lunch, Dinner)), 'potato' ); /*-------------------+-------------------------+------------------+ | Breakfast | Lunch | Dinner | +-------------------+-------------------------+------------------+ | Potato pancakes | Toasted cheese sandwich | Beef stroganoff | +-------------------+-------------------------+------------------*/ The following query searches for the value lunch in the JSON {"lunch":"soup"} and returns FALSE because the default json_scope is "JSON_VALUES", and lunch is a JSON key, not a JSON value.
SELECT CONTAINS_SUBSTR(JSON '{"lunch":"soup"}',"lunch") AS result; /*--------+ | result | +--------+ | FALSE | +--------*/ The following query searches for the value lunch in the values of the JSON {"lunch":"soup"} and returns FALSE because lunch is a JSON key, not a JSON value.
SELECT CONTAINS_SUBSTR(JSON '{"lunch":"soup"}', "lunch", json_scope=>"JSON_VALUES") AS result; /*--------+ | result | +--------+ | FALSE | +--------*/ The following query searches for the value lunch in the keys and values of the JSON {"lunch":"soup"} and returns TRUE because lunch is a JSON key.
SELECT CONTAINS_SUBSTR(JSON '{"lunch":"soup"}', "lunch", json_scope=>"JSON_KEYS_AND_VALUES") AS result; /*--------+ | result | +--------+ | TRUE | +--------*/ The following query searches for the value lunch in the keys of the JSON {"lunch":"soup"} and returns TRUE because lunch is a JSON key.
SELECT CONTAINS_SUBSTR(JSON '{"lunch":"soup"}', "lunch", json_scope=>"JSON_KEYS") AS result; /*--------+ | result | +--------+ | TRUE | +--------*/ EDIT_DISTANCE
EDIT_DISTANCE( value1, value2, [ max_distance => max_distance_value ] ) Description
Computes the Levenshtein distance between two STRING or BYTES values.
Definitions
value1: The firstSTRINGorBYTESvalue to compare.value2: The secondSTRINGorBYTESvalue to compare.max_distance: A named argument with aINT64value that's greater than or equal to zero. Represents the maximum distance between the two values to compute.If this distance is exceeded, the function returns this value. The default value for this argument is the maximum size of
value1andvalue2.
Details
If value1 or value2 is NULL, NULL is returned.
You can only compare values of the same type. Otherwise, an error is produced.
Return type
INT64
Examples
In the following example, the first character in both strings is different:
SELECT EDIT_DISTANCE('a', 'b') AS results; /*---------+ | results | +---------+ | 1 | +---------*/ In the following example, the first and second characters in both strings are different:
SELECT EDIT_DISTANCE('aa', 'b') AS results; /*---------+ | results | +---------+ | 2 | +---------*/ In the following example, only the first character in both strings is different:
SELECT EDIT_DISTANCE('aa', 'ba') AS results; /*---------+ | results | +---------+ | 1 | +---------*/ In the following example, the last six characters are different, but because the maximum distance is 2, this function exits early and returns 2, the maximum distance:
SELECT EDIT_DISTANCE('abcdefg', 'a', max_distance => 2) AS results; /*---------+ | results | +---------+ | 2 | +---------*/ ENDS_WITH
ENDS_WITH(value, suffix) Description
Takes two STRING or BYTES values. Returns TRUE if suffix is a suffix of value.
This function supports specifying collation.
Return type
BOOL
Examples
SELECT ENDS_WITH('apple', 'e') as example /*---------+ | example | +---------+ | True | +---------*/ FORMAT
FORMAT(format_string_expression, data_type_expression[, ...]) Description
FORMAT formats a data type expression as a string.
format_string_expression: Can contain zero or more format specifiers. Each format specifier is introduced by the%symbol, and must map to one or more of the remaining arguments. In general, this is a one-to-one mapping, except when the*specifier is present. For example,%.*imaps to two arguments—a length argument and a signed integer argument. If the number of arguments related to the format specifiers isn't the same as the number of arguments, an error occurs.data_type_expression: The value to format as a string. This can be any GoogleSQL data type.
Return type
STRING
Examples
| Description | Statement | Result |
|---|---|---|
| Simple integer | FORMAT('%d', 10) | 10 |
| Integer with left blank padding | FORMAT('|%10d|', 11) | | 11| |
| Integer with left zero padding | FORMAT('+%010d+', 12) | +0000000012+ |
| Integer with commas | FORMAT("%'d", 123456789) | 123,456,789 |
| STRING | FORMAT('-%s-', 'abcd efg') | -abcd efg- |
| FLOAT64 | FORMAT('%f %E', 1.1, 2.2) | 1.100000 2.200000E+00 |
| DATE | FORMAT('%t', date '2015-09-01') | 2015-09-01 |
| TIMESTAMP | FORMAT('%t', timestamp '2015-09-01 12:34:56 America/Los_Angeles') | 2015‑09‑01 19:34:56+00 |
The FORMAT() function doesn't provide fully customizable formatting for all types and values, nor formatting that's sensitive to locale.
If custom formatting is necessary for a type, you must first format it using type-specific format functions, such as FORMAT_DATE() or FORMAT_TIMESTAMP(). For example:
SELECT FORMAT('date: %s!', FORMAT_DATE('%B %d, %Y', date '2015-01-02')); Returns
date: January 02, 2015! Supported format specifiers
%[flags][width][.precision]specifier A format specifier adds formatting when casting a value to a string. It can optionally contain these sub-specifiers:
Additional information about format specifiers:
- %g and %G behavior
- %p and %P behavior
- %t and %T behavior
- Error conditions
- NULL argument handling
- Additional semantic rules
Format specifiers
| Specifier | Description | Examples | Types |
d or i | Decimal integer | 392 | INT64 |
o | Octal Note: If an INT64 value is negative, an error is produced. | 610 | INT64 |
x | Hexadecimal integer Note: If an INT64 value is negative, an error is produced. | 7fa | INT64 |
X | Hexadecimal integer (uppercase) Note: If an INT64 value is negative, an error is produced. | 7FA | INT64 |
f | Decimal notation, in [-](integer part).(fractional part) for finite values, and in lowercase for non-finite values | 392.650000 inf nan | NUMERICBIGNUMERICFLOAT64 |
F | Decimal notation, in [-](integer part).(fractional part) for finite values, and in uppercase for non-finite values | 392.650000 INF NAN | NUMERICBIGNUMERICFLOAT64 |
e | Scientific notation (mantissa/exponent), lowercase | 3.926500e+02 inf nan | NUMERICBIGNUMERICFLOAT64 |
E | Scientific notation (mantissa/exponent), uppercase | 3.926500E+02 INF NAN | NUMERICBIGNUMERICFLOAT64 |
g | Either decimal notation or scientific notation, depending on the input value's exponent and the specified precision. Lowercase. See %g and %G behavior for details. | 392.65 3.9265e+07 inf nan | NUMERICBIGNUMERICFLOAT64 |
G | Either decimal notation or scientific notation, depending on the input value's exponent and the specified precision. Uppercase. See %g and %G behavior for details. | 392.65 3.9265E+07 INF NAN | NUMERICBIGNUMERICFLOAT64 |
p | Produces a one-line printable string representing JSON. See %p and %P behavior. | {"month":10,"year":2019} | JSON |
P | Produces a multi-line printable string representing JSON. See %p and %P behavior. | { "month": 10, "year": 2019 } | JSON |
s | String of characters | sample | STRING |
t | Returns a printable string representing the value. Often looks similar to casting the argument to STRING. See %t and %T behavior. | sample 2014‑01‑01 | Any type |
T | Produces a string that's a valid GoogleSQL constant with a similar type to the value's type (maybe wider, or maybe string). See %t and %T behavior. | 'sample' b'bytes sample' 1234 2.3 date '2014‑01‑01' | Any type |
% | '%%' produces a single '%' | % | n/a |
The format specifier can optionally contain the sub-specifiers identified above in the specifier prototype.
These sub-specifiers must comply with the following specifications.
Flags
| Flags | Description |
- | Left-justify within the given field width; Right justification is the default (see width sub-specifier) |
+ | Forces to precede the result with a plus or minus sign (+ or -) even for positive numbers. By default, only negative numbers are preceded with a - sign |
| <space> | If no sign is going to be written, a blank space is inserted before the value |
# |
|
0 | Left-pads the number with zeroes (0) instead of spaces when padding is specified (see width sub-specifier) |
' | Formats integers using the appropriating grouping character. For example:
This flag is only relevant for decimal, hex, and octal values. |
Flags may be specified in any order. Duplicate flags aren't an error. When flags aren't relevant for some element type, they are ignored.
Width
| Width | Description |
| <number> | Minimum number of characters to be printed. If the value to be printed is shorter than this number, the result is padded with blank spaces. The value isn't truncated even if the result is larger |
* | The width isn't specified in the format string, but as an additional integer value argument preceding the argument that has to be formatted |
Precision
| Precision | Description |
.<number> |
|
.* | The precision isn't specified in the format string, but as an additional integer value argument preceding the argument that has to be formatted |
%g and %G behavior
The %g and %G format specifiers choose either the decimal notation (like the %f and %F specifiers) or the scientific notation (like the %e and %E specifiers), depending on the input value's exponent and the specified precision.
Let p stand for the specified precision (defaults to 6; 1 if the specified precision is less than 1). The input value is first converted to scientific notation with precision = (p - 1). If the resulting exponent part x is less than -4 or no less than p, the scientific notation with precision = (p - 1) is used; otherwise the decimal notation with precision = (p - 1 - x) is used.
Unless # flag is present, the trailing zeros after the decimal point are removed, and the decimal point is also removed if there is no digit after it.
%p and %P behavior
The %p format specifier produces a one-line printable string. The %P format specifier produces a multi-line printable string. You can use these format specifiers with the following data types:
| Type | %p | %P |
| JSON | JSON input: JSON ' { "month": 10, "year": 2019 } 'Produces a one-line printable string representing JSON: {"month":10,"year":2019} | JSON input: JSON ' { "month": 10, "year": 2019 } 'Produces a multi-line printable string representing JSON: { "month": 10, "year": 2019 } |
%t and %T behavior
The %t and %T format specifiers are defined for all types. The width, precision, and flags act as they do for %s: the width is the minimum width and the STRING will be padded to that size, and precision is the maximum width of content to show and the STRING will be truncated to that size, prior to padding to width.
The %t specifier is always meant to be a readable form of the value.
The %T specifier is always a valid SQL literal of a similar type, such as a wider numeric type. The literal will not include casts or a type name, except for the special case of non-finite floating point values.
The STRING is formatted as follows:
| Type | %t | %T |
NULL of any type | NULL | NULL |
INT64 | 123 | 123 |
| NUMERIC | 123.0 (always with .0) | NUMERIC "123.0" |
| FLOAT64 | 123.0 (always with .0) 123e+10 inf-infNaN | 123.0 (always with .0) 123e+10 CAST("inf" AS <type>) CAST("-inf" AS <type>) CAST("nan" AS <type>) |
| STRING | unquoted string value | quoted string literal |
| BYTES | unquoted escaped bytes e.g., abc\x01\x02 | quoted bytes literal e.g., b"abc\x01\x02" |
| BOOL | boolean value | boolean value |
| DATE | 2011-02-03 | DATE "2011-02-03" |
| TIMESTAMP | 2011-02-03 04:05:06+00 | TIMESTAMP "2011-02-03 04:05:06+00" |
| INTERVAL | 1-2 3 4:5:6.789 | INTERVAL "1-2 3 4:5:6.789" YEAR TO SECOND |
| ARRAY | [value, value, ...] where values are formatted with %t | [value, value, ...] where values are formatted with %T |
| STRUCT | (value, value, ...) where fields are formatted with %t | (value, value, ...) where fields are formatted with %T Special cases: Zero fields: STRUCT() One field: STRUCT(value) |
| JSON | one-line printable string representing JSON.{"name":"apple","stock":3} | one-line printable string representing a JSON literal.JSON '{"name":"apple","stock":3}' |
Error conditions
If a format specifier is invalid, or isn't compatible with the related argument type, or the wrong number or arguments are provided, then an error is produced. For example, the following <format_string> expressions are invalid:
FORMAT('%s', 1) FORMAT('%') NULL argument handling
A NULL format string results in a NULL output STRING. Any other arguments are ignored in this case.
The function generally produces a NULL value if a NULL argument is present. For example, FORMAT('%i', NULL_expression) produces a NULL STRING as output.
However, there are some exceptions: if the format specifier is %t or %T (both of which produce STRINGs that effectively match CAST and literal value semantics), a NULL value produces 'NULL' (without the quotes) in the result STRING. For example, the function:
FORMAT('00-%t-00', NULL_expression); Returns
00-NULL-00 Additional semantic rules
FLOAT64 values can be +/-inf or NaN. When an argument has one of those values, the result of the format specifiers %f, %F, %e, %E, %g, %G, and %t are inf, -inf, or nan (or the same in uppercase) as appropriate. This is consistent with how GoogleSQL casts these values to STRING. For %T, GoogleSQL returns quoted strings for FLOAT64 values that don't have non-string literal representations.
FROM_BASE32
FROM_BASE32(string_expr) Description
Converts the base32-encoded input string_expr into BYTES format. To convert BYTES to a base32-encoded STRING, use TO_BASE32.
Return type
BYTES
Example
SELECT FROM_BASE32('MFRGGZDF74======') AS byte_data; -- Note that the result of FROM_BASE32 is of type BYTES, displayed as a base64-encoded string. /*-----------+ | byte_data | +-----------+ | YWJjZGX/ | +-----------*/ FROM_BASE64
FROM_BASE64(string_expr) Description
Converts the base64-encoded input string_expr into BYTES format. To convert BYTES to a base64-encoded STRING, use TO_BASE64.
There are several base64 encodings in common use that vary in exactly which alphabet of 65 ASCII characters are used to encode the 64 digits and padding. See RFC 4648 for details. This function expects the alphabet [A-Za-z0-9+/=].
Return type
BYTES
Example
SELECT FROM_BASE64('/+A=') AS byte_data; -- Note that the result of FROM_BASE64 is of type BYTES, displayed as a base64-encoded string. /*-----------+ | byte_data | +-----------+ | /+A= | +-----------*/ To work with an encoding using a different base64 alphabet, you might need to compose FROM_BASE64 with the REPLACE function. For instance, the base64url url-safe and filename-safe encoding commonly used in web programming uses -_= as the last characters rather than +/=. To decode a base64url-encoded string, replace - and _ with + and / respectively.
SELECT FROM_BASE64(REPLACE(REPLACE('_-A=', '-', '+'), '_', '/')) AS binary; -- Note that the result of FROM_BASE64 is of type BYTES, displayed as a base64-encoded string. /*--------+ | binary | +--------+ | /+A= | +--------*/ FROM_HEX
FROM_HEX(string) Description
Converts a hexadecimal-encoded STRING into BYTES format. Returns an error if the input STRING contains characters outside the range (0..9, A..F, a..f). The lettercase of the characters doesn't matter. If the input STRING has an odd number of characters, the function acts as if the input has an additional leading 0. To convert BYTES to a hexadecimal-encoded STRING, use TO_HEX.
Return type
BYTES
Example
WITH Input AS ( SELECT '00010203aaeeefff' AS hex_str UNION ALL SELECT '0AF' UNION ALL SELECT '666f6f626172' ) SELECT hex_str, FROM_HEX(hex_str) AS bytes_str FROM Input; -- Note that the result of FROM_HEX is of type BYTES, displayed as a base64-encoded string. /*------------------+--------------+ | hex_str | bytes_str | +------------------+--------------+ | 0AF | AK8= | | 00010203aaeeefff | AAECA6ru7/8= | | 666f6f626172 | Zm9vYmFy | +------------------+--------------*/ INITCAP
INITCAP(value[, delimiters]) Description
Takes a STRING and returns it with the first character in each word in uppercase and all other characters in lowercase. Non-alphabetic characters remain the same.
delimiters is an optional string argument that's used to override the default set of characters used to separate words. If delimiters isn't specified, it defaults to the following characters:
<whitespace> [ ] ( ) { } / | \ < > ! ? @ " ^ # $ & ~ _ , . : ; * % + -
If value or delimiters is NULL, the function returns NULL.
Return type
STRING
Examples
SELECT 'Hello World-everyone!' AS value, INITCAP('Hello World-everyone!') AS initcap_value /*-------------------------------+-------------------------------+ | value | initcap_value | +-------------------------------+-------------------------------+ | Hello World-everyone! | Hello World-Everyone! | +-------------------------------+-------------------------------*/ SELECT 'Apples1oranges2pears' as value, '12' AS delimiters, INITCAP('Apples1oranges2pears' , '12') AS initcap_value /*----------------------+------------+----------------------+ | value | delimiters | initcap_value | +----------------------+------------+----------------------+ | Apples1oranges2pears | 12 | Apples1Oranges2Pears | +----------------------+------------+----------------------*/ INSTR
INSTR(value, subvalue[, position[, occurrence]]) Description
Returns the lowest 1-based position of subvalue in value. value and subvalue must be the same type, either STRING or BYTES.
If position is specified, the search starts at this position in value, otherwise it starts at 1, which is the beginning of value. If position is negative, the function searches backwards from the end of value, with -1 indicating the last character. position is of type INT64 and can't be 0.
If occurrence is specified, the search returns the position of a specific instance of subvalue in value. If not specified, occurrence defaults to 1 and returns the position of the first occurrence. For occurrence > 1, the function includes overlapping occurrences. occurrence is of type INT64 and must be positive.
This function supports specifying collation.
Returns 0 if:
- No match is found.
- If
occurrenceis greater than the number of matches found. - If
positionis greater than the length ofvalue.
Returns NULL if:
- Any input argument is
NULL.
Returns an error if:
positionis0.occurrenceis0or negative.
Return type
INT64
Examples
SELECT 'banana' AS value, 'an' AS subvalue, 1 AS position, 1 AS occurrence, INSTR('banana', 'an', 1, 1) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | an | 1 | 1 | 2 | +--------------+--------------+----------+------------+-------*/ SELECT 'banana' AS value, 'an' AS subvalue, 1 AS position, 2 AS occurrence, INSTR('banana', 'an', 1, 2) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | an | 1 | 2 | 4 | +--------------+--------------+----------+------------+-------*/ SELECT 'banana' AS value, 'an' AS subvalue, 1 AS position, 3 AS occurrence, INSTR('banana', 'an', 1, 3) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | an | 1 | 3 | 0 | +--------------+--------------+----------+------------+-------*/ SELECT 'banana' AS value, 'an' AS subvalue, 3 AS position, 1 AS occurrence, INSTR('banana', 'an', 3, 1) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | an | 3 | 1 | 4 | +--------------+--------------+----------+------------+-------*/ SELECT 'banana' AS value, 'an' AS subvalue, -1 AS position, 1 AS occurrence, INSTR('banana', 'an', -1, 1) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | an | -1 | 1 | 4 | +--------------+--------------+----------+------------+-------*/ SELECT 'banana' AS value, 'an' AS subvalue, -3 AS position, 1 AS occurrence, INSTR('banana', 'an', -3, 1) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | an | -3 | 1 | 4 | +--------------+--------------+----------+------------+-------*/ SELECT 'banana' AS value, 'ann' AS subvalue, 1 AS position, 1 AS occurrence, INSTR('banana', 'ann', 1, 1) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | banana | ann | 1 | 1 | 0 | +--------------+--------------+----------+------------+-------*/ SELECT 'helloooo' AS value, 'oo' AS subvalue, 1 AS position, 1 AS occurrence, INSTR('helloooo', 'oo', 1, 1) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | helloooo | oo | 1 | 1 | 5 | +--------------+--------------+----------+------------+-------*/ SELECT 'helloooo' AS value, 'oo' AS subvalue, 1 AS position, 2 AS occurrence, INSTR('helloooo', 'oo', 1, 2) AS instr; /*--------------+--------------+----------+------------+-------+ | value | subvalue | position | occurrence | instr | +--------------+--------------+----------+------------+-------+ | helloooo | oo | 1 | 2 | 6 | +--------------+--------------+----------+------------+-------*/ LEFT
LEFT(value, length) Description
Returns a STRING or BYTES value that consists of the specified number of leftmost characters or bytes from value. The length is an INT64 that specifies the length of the returned value. If value is of type BYTES, length is the number of leftmost bytes to return. If value is STRING, length is the number of leftmost characters to return.
If length is 0, an empty STRING or BYTES value will be returned. If length is negative, an error will be returned. If length exceeds the number of characters or bytes from value, the original value will be returned.
Return type
STRING or BYTES
Examples
SELECT LEFT('banana', 3) AS results /*---------+ | results | +--------+ | ban | +---------*/ SELECT LEFT(b'\xab\xcd\xef\xaa\xbb', 3) AS results -- Note that the result of LEFT is of type BYTES, displayed as a base64-encoded string. /*---------+ | results | +---------+ | q83v | +---------*/ LENGTH
LENGTH(value) Description
Returns the length of the STRING or BYTES value. The returned value is in characters for STRING arguments and in bytes for the BYTES argument.
Return type
INT64
Examples
SELECT LENGTH('абвгд') AS string_example, LENGTH(CAST('абвгд' AS BYTES)) AS bytes_example; /*----------------+---------------+ | string_example | bytes_example | +----------------+---------------+ | 5 | 10 | +----------------+---------------*/ LOWER
LOWER(value) Description
For STRING arguments, returns the original string with all alphabetic characters in lowercase. Mapping between lowercase and uppercase is done according to the Unicode Character Database without taking into account language-specific mappings.
For BYTES arguments, the argument is treated as ASCII text, with all bytes greater than 127 left intact.
Return type
STRING or BYTES
Examples
SELECT LOWER('FOO BAR BAZ') AS example FROM items; /*-------------+ | example | +-------------+ | foo bar baz | +-------------*/ LPAD
LPAD(original_value, return_length[, pattern]) Description
Returns a STRING or BYTES value that consists of original_value prepended with pattern. The return_length is an INT64 that specifies the length of the returned value. If original_value is of type BYTES, return_length is the number of bytes. If original_value is of type STRING, return_length is the number of characters.
The default value of pattern is a blank space.
Both original_value and pattern must be the same data type.
If return_length is less than or equal to the original_value length, this function returns the original_value value, truncated to the value of return_length. For example, LPAD('hello world', 7); returns 'hello w'.
If original_value, return_length, or pattern is NULL, this function returns NULL.
This function returns an error if:
return_lengthis negativepatternis empty
Return type
STRING or BYTES
Examples
SELECT FORMAT('%T', LPAD('c', 5)) AS results /*---------+ | results | +---------+ | " c" | +---------*/ SELECT LPAD('b', 5, 'a') AS results /*---------+ | results | +---------+ | aaaab | +---------*/ SELECT LPAD('abc', 10, 'ghd') AS results /*------------+ | results | +------------+ | ghdghdgabc | +------------*/ SELECT LPAD('abc', 2, 'd') AS results /*---------+ | results | +---------+ | ab | +---------*/ SELECT FORMAT('%T', LPAD(b'abc', 10, b'ghd')) AS results /*---------------+ | results | +---------------+ | b"ghdghdgabc" | +---------------*/ LTRIM
LTRIM(value1[, value2]) Description
Identical to TRIM, but only removes leading characters.
Return type
STRING or BYTES
Examples
SELECT CONCAT('#', LTRIM(' apple '), '#') AS example /*-------------+ | example | +-------------+ | #apple # | +-------------*/ SELECT LTRIM('***apple***', '*') AS example /*-----------+ | example | +-----------+ | apple*** | +-----------*/ SELECT LTRIM('xxxapplexxx', 'xyz') AS example /*-----------+ | example | +-----------+ | applexxx | +-----------*/ NORMALIZE
NORMALIZE(value[, normalization_mode]) Description
Takes a string value and returns it as a normalized string. If you don't provide a normalization mode, NFC is used.
Normalization is used to ensure that two strings are equivalent. Normalization is often used in situations in which two strings render the same on the screen but have different Unicode code points.
NORMALIZE supports four optional normalization modes:
| Value | Name | Description |
|---|---|---|
NFC | Normalization Form Canonical Composition | Decomposes and recomposes characters by canonical equivalence. |
NFKC | Normalization Form Compatibility Composition | Decomposes characters by compatibility, then recomposes them by canonical equivalence. |
NFD | Normalization Form Canonical Decomposition | Decomposes characters by canonical equivalence, and multiple combining characters are arranged in a specific order. |
NFKD | Normalization Form Compatibility Decomposition | Decomposes characters by compatibility, and multiple combining characters are arranged in a specific order. |
Return type
STRING
Examples
The following example normalizes different language characters:
SELECT NORMALIZE('\u00ea') as a, NORMALIZE('\u0065\u0302') as b, NORMALIZE('\u00ea') = NORMALIZE('\u0065\u0302') as normalized; /*---+---+------------+ | a | b | normalized | +---+---+------------+ | ê | ê | TRUE | +---+---+------------*/ The following examples normalize different space characters:
SELECT NORMALIZE('Raha\u2004Mahan', NFKC) AS normalized_name /*-----------------+ | normalized_name | +-----------------+ | Raha Mahan | +-----------------*/ SELECT NORMALIZE('Raha\u2005Mahan', NFKC) AS normalized_name /*-----------------+ | normalized_name | +-----------------+ | Raha Mahan | +-----------------*/ SELECT NORMALIZE('Raha\u2006Mahan', NFKC) AS normalized_name /*-----------------+ | normalized_name | +-----------------+ | Raha Mahan | +-----------------*/ SELECT NORMALIZE('Raha Mahan', NFKC) AS normalized_name /*-----------------+ | normalized_name | +-----------------+ | Raha Mahan | +-----------------*/ NORMALIZE_AND_CASEFOLD
NORMALIZE_AND_CASEFOLD(value[, normalization_mode]) Description
Takes a string value and returns it as a normalized string. If you don't provide a normalization mode, NFC is used.
Normalization is used to ensure that two strings are equivalent. Normalization is often used in situations in which two strings render the same on the screen but have different Unicode code points.
Case folding is used for the caseless comparison of strings. If you need to compare strings and case shouldn't be considered, use NORMALIZE_AND_CASEFOLD, otherwise use NORMALIZE.
NORMALIZE_AND_CASEFOLD supports four optional normalization modes:
| Value | Name | Description |
|---|---|---|
NFC | Normalization Form Canonical Composition | Decomposes and recomposes characters by canonical equivalence. |
NFKC | Normalization Form Compatibility Composition | Decomposes characters by compatibility, then recomposes them by canonical equivalence. |
NFD | Normalization Form Canonical Decomposition | Decomposes characters by canonical equivalence, and multiple combining characters are arranged in a specific order. |
NFKD | Normalization Form Compatibility Decomposition | Decomposes characters by compatibility, and multiple combining characters are arranged in a specific order. |
Return type
STRING
Examples
SELECT NORMALIZE('The red barn') = NORMALIZE('The Red Barn') AS normalized, NORMALIZE_AND_CASEFOLD('The red barn') = NORMALIZE_AND_CASEFOLD('The Red Barn') AS normalized_with_case_folding; /*------------+------------------------------+ | normalized | normalized_with_case_folding | +------------+------------------------------+ | FALSE | TRUE | +------------+------------------------------*/ SELECT '\u2168' AS a, 'IX' AS b, NORMALIZE_AND_CASEFOLD('\u2168', NFD)=NORMALIZE_AND_CASEFOLD('IX', NFD) AS nfd, NORMALIZE_AND_CASEFOLD('\u2168', NFC)=NORMALIZE_AND_CASEFOLD('IX', NFC) AS nfc, NORMALIZE_AND_CASEFOLD('\u2168', NFKD)=NORMALIZE_AND_CASEFOLD('IX', NFKD) AS nkfd, NORMALIZE_AND_CASEFOLD('\u2168', NFKC)=NORMALIZE_AND_CASEFOLD('IX', NFKC) AS nkfc; /*---+----+-------+-------+------+------+ | a | b | nfd | nfc | nkfd | nkfc | +---+----+-------+-------+------+------+ | Ⅸ | IX | false | false | true | true | +---+----+-------+-------+------+------*/ SELECT '\u0041\u030A' AS a, '\u00C5' AS b, NORMALIZE_AND_CASEFOLD('\u0041\u030A', NFD)=NORMALIZE_AND_CASEFOLD('\u00C5', NFD) AS nfd, NORMALIZE_AND_CASEFOLD('\u0041\u030A', NFC)=NORMALIZE_AND_CASEFOLD('\u00C5', NFC) AS nfc, NORMALIZE_AND_CASEFOLD('\u0041\u030A', NFKD)=NORMALIZE_AND_CASEFOLD('\u00C5', NFKD) AS nkfd, NORMALIZE_AND_CASEFOLD('\u0041\u030A', NFKC)=NORMALIZE_AND_CASEFOLD('\u00C5', NFKC) AS nkfc; /*---+----+-------+-------+------+------+ | a | b | nfd | nfc | nkfd | nkfc | +---+----+-------+-------+------+------+ | Å | Å | true | true | true | true | +---+----+-------+-------+------+------*/ OCTET_LENGTH
OCTET_LENGTH(value) Alias for BYTE_LENGTH.
REGEXP_CONTAINS
REGEXP_CONTAINS(value, regexp) Description
Returns TRUE if value is a partial match for the regular expression, regexp.
If the regexp argument is invalid, the function returns an error.
You can search for a full match by using ^ (beginning of text) and $ (end of text). Due to regular expression operator precedence, it's good practice to use parentheses around everything between ^ and $.
Return type
BOOL
Examples
The following queries check to see if an email is valid:
SELECT '[email protected]' AS email, REGEXP_CONTAINS('[email protected]', r'@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+') AS is_valid /*-----------------+----------+ | email | is_valid | +-----------------+----------+ | [email protected] | TRUE | +-----------------+----------*/ ``` ```googlesql SELECT 'www.example.net' AS email, REGEXP_CONTAINS('www.example.net', r'@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+') AS is_valid /*-----------------+----------+ | email | is_valid | +-----------------+----------+ | www.example.net | FALSE | +-----------------+----------*/ ``` The following queries check to see if an email is valid. They perform a full match, using `^` and `$`. Due to regular expression operator precedence, it's good practice to use parentheses around everything between `^` and `$`. ```googlesql SELECT '[email protected]' AS email, REGEXP_CONTAINS('[email protected]', r'^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)$') AS valid_email_address, REGEXP_CONTAINS('[email protected]', r'^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org$') AS without_parentheses; /*----------------+---------------------+---------------------+ | email | valid_email_address | without_parentheses | +----------------+---------------------+---------------------+ | [email protected] | true | true | +----------------+---------------------+---------------------*/ SELECT '[email protected]' AS email, REGEXP_CONTAINS('[email protected]', r'^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)$') AS valid_email_address, REGEXP_CONTAINS('[email protected]', r'^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org$') AS without_parentheses; /*----------------+---------------------+---------------------+ | email | valid_email_address | without_parentheses | +----------------+---------------------+---------------------+ | [email protected] | false | true | +----------------+---------------------+---------------------*/ SELECT '[email protected]' AS email, REGEXP_CONTAINS('[email protected]', r'^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)$') AS valid_email_address, REGEXP_CONTAINS('[email protected]', r'^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org$') AS without_parentheses; /*----------------+---------------------+---------------------+ | email | valid_email_address | without_parentheses | +----------------+---------------------+---------------------+ | [email protected] | true | true | +----------------+---------------------+---------------------*/ SELECT '[email protected]' AS email, REGEXP_CONTAINS('[email protected]', r'^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)$') AS valid_email_address, REGEXP_CONTAINS('[email protected]', r'^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org$') AS without_parentheses; /*----------------+---------------------+---------------------+ | email | valid_email_address | without_parentheses | +----------------+---------------------+---------------------+ | [email protected] | false | true | +----------------+---------------------+---------------------*/ SELECT '[email protected]' AS email, REGEXP_CONTAINS('[email protected]', r'^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)$') AS valid_email_address, REGEXP_CONTAINS('[email protected]', r'^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org$') AS without_parentheses; /*----------------+---------------------+---------------------+ | email | valid_email_address | without_parentheses | +----------------+---------------------+---------------------+ | [email protected] | false | false | +----------------+---------------------+---------------------*/ REGEXP_EXTRACT
REGEXP_EXTRACT(value, regexp[, position[, occurrence]]) Description
Returns the substring in value that matches the re2 regular expression, regexp. Returns NULL if there is no match.
If the regular expression contains a capturing group ((...)), and there is a match for that capturing group, that match is returned. If there are multiple matches for a capturing group, the first match is returned.
If position is specified, the search starts at this position in value, otherwise it starts at the beginning of value. The position must be a positive integer and can't be 0. If position is greater than the length of value, NULL is returned.
If occurrence is specified, the search returns a specific occurrence of the regexp in value, otherwise returns the first match. If occurrence is greater than the number of matches found, NULL is returned. For occurrence > 1, the function searches for additional occurrences beginning with the character following the previous occurrence.
Returns an error if:
- The regular expression is invalid
- The regular expression has more than one capturing group
- The
positionisn't a positive integer - The
occurrenceisn't a positive integer
Return type
STRING or BYTES
Examples
SELECT REGEXP_EXTRACT('[email protected]', r'^[a-zA-Z0-9_.+-]+') AS user_name /*-----------+ | user_name | +-----------+ | foo | +-----------*/ SELECT REGEXP_EXTRACT('[email protected]', r'^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.([a-zA-Z0-9-.]+$)') /*------------------+ | top_level_domain | +------------------+ | com | +------------------*/ SELECT REGEXP_EXTRACT('ab', '.b') AS result_a, REGEXP_EXTRACT('ab', '(.)b') AS result_b, REGEXP_EXTRACT('xyztb', '(.)+b') AS result_c, REGEXP_EXTRACT('ab', '(z)?b') AS result_d /*-------------------------------------------+ | result_a | result_b | result_c | result_d | +-------------------------------------------+ | ab | a | t | NULL | +-------------------------------------------*/ WITH example AS (SELECT 'Hello Helloo and Hellooo' AS value, 'H?ello+' AS regex, 1 as position, 1 AS occurrence UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 1, 2 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 1, 3 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 1, 4 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 2, 1 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 3, 1 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 3, 2 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 3, 3 UNION ALL SELECT 'Hello Helloo and Hellooo', 'H?ello+', 20, 1 UNION ALL SELECT 'cats&dogs&rabbits' ,'\\w+&', 1, 2 UNION ALL SELECT 'cats&dogs&rabbits', '\\w+&', 2, 3 ) SELECT value, regex, position, occurrence, REGEXP_EXTRACT(value, regex, position, occurrence) AS regexp_value FROM example; /*--------------------------+---------+----------+------------+--------------+ | value | regex | position | occurrence | regexp_value | +--------------------------+---------+----------+------------+--------------+ | Hello Helloo and Hellooo | H?ello+ | 1 | 1 | Hello | | Hello Helloo and Hellooo | H?ello+ | 1 | 2 | Helloo | | Hello Helloo and Hellooo | H?ello+ | 1 | 3 | Hellooo | | Hello Helloo and Hellooo | H?ello+ | 1 | 4 | NULL | | Hello Helloo and Hellooo | H?ello+ | 2 | 1 | ello | | Hello Helloo and Hellooo | H?ello+ | 3 | 1 | Helloo | | Hello Helloo and Hellooo | H?ello+ | 3 | 2 | Hellooo | | Hello Helloo and Hellooo | H?ello+ | 3 | 3 | NULL | | Hello Helloo and Hellooo | H?ello+ | 20 | 1 | NULL | | cats&dogs&rabbits | \w+& | 1 | 2 | dogs& | | cats&dogs&rabbits | \w+& | 2 | 3 | NULL | +--------------------------+---------+----------+------------+--------------*/ REGEXP_EXTRACT_ALL
REGEXP_EXTRACT_ALL(value, regexp) Description
Returns an array of all substrings of value that match the re2 regular expression, regexp. Returns an empty array if there is no match.
If the regular expression contains a capturing group ((...)), and there is a match for that capturing group, that match is added to the results.
The REGEXP_EXTRACT_ALL function only returns non-overlapping matches. For example, using this function to extract ana from banana returns only one substring, not two.
Returns an error if:
- The regular expression is invalid
- The regular expression has more than one capturing group
Return type
ARRAY<STRING> or ARRAY<BYTES>
Examples
SELECT REGEXP_EXTRACT_ALL('Try `func(x)` or `func(y)`', '`(.+?)`') AS example /*--------------------+ | example | +--------------------+ | [func(x), func(y)] | +--------------------*/ REGEXP_INSTR
REGEXP_INSTR(source_value, regexp [, position[, occurrence, [occurrence_position]]]) Description
Returns the lowest 1-based position of a regular expression, regexp, in source_value. source_value and regexp must be the same type, either STRING or BYTES.
If position is specified, the search starts at this position in source_value, otherwise it starts at 1, which is the beginning of source_value. position is of type INT64 and must be positive.
If occurrence is specified, the search returns the position of a specific instance of regexp in source_value. If not specified, occurrence defaults to 1 and returns the position of the first occurrence. For occurrence > 1, the function searches for the next, non-overlapping occurrence. occurrence is of type INT64 and must be positive.
You can optionally use occurrence_position to specify where a position in relation to an occurrence starts. Your choices are:
0: Returns the start position ofoccurrence.1: Returns the end position ofoccurrence+1. If the end of the occurrence is at the end ofsource_value,LENGTH(source_value) + 1is returned.
Returns 0 if:
- No match is found.
- If
occurrenceis greater than the number of matches found. - If
positionis greater than the length ofsource_value. - The regular expression is empty.
Returns NULL if:
positionisNULL.occurrenceisNULL.
Returns an error if:
positionis0or negative.occurrenceis0or negative.occurrence_positionis neither0nor1.- The regular expression is invalid.
- The regular expression has more than one capturing group.
Return type
INT64
Examples
SELECT REGEXP_INSTR('ab@cd-ef', '@[^-]*') AS instr_a, REGEXP_INSTR('ab@d-ef', '@[^-]*') AS instr_b, REGEXP_INSTR('abc@cd-ef', '@[^-]*') AS instr_c, REGEXP_INSTR('abc-ef', '@[^-]*') AS instr_d, /*---------------------------------------+ | instr_a | instr_b | instr_c | instr_d | +---------------------------------------+ | 3 | 3 | 4 | 0 | +---------------------------------------*/ SELECT REGEXP_INSTR('a@cd-ef b@cd-ef', '@[^-]*', 1) AS instr_a, REGEXP_INSTR('a@cd-ef b@cd-ef', '@[^-]*', 2) AS instr_b, REGEXP_INSTR('a@cd-ef b@cd-ef', '@[^-]*', 3) AS instr_c, REGEXP_INSTR('a@cd-ef b@cd-ef', '@[^-]*', 4) AS instr_d, /*---------------------------------------+ | instr_a | instr_b | instr_c | instr_d | +---------------------------------------+ | 2 | 2 | 10 | 10 | +---------------------------------------*/ SELECT REGEXP_INSTR('a@cd-ef b@cd-ef c@cd-ef', '@[^-]*', 1, 1) AS instr_a, REGEXP_INSTR('a@cd-ef b@cd-ef c@cd-ef', '@[^-]*', 1, 2) AS instr_b, REGEXP_INSTR('a@cd-ef b@cd-ef c@cd-ef', '@[^-]*', 1, 3) AS instr_c /*-----------------------------+ | instr_a | instr_b | instr_c | +-----------------------------+ | 2 | 10 | 18 | +-----------------------------*/ SELECT REGEXP_INSTR('a@cd-ef', '@[^-]*', 1, 1, 0) AS instr_a, REGEXP_INSTR('a@cd-ef', '@[^-]*', 1, 1, 1) AS instr_b /*-------------------+ | instr_a | instr_b | +-------------------+ | 2 | 5 | +-------------------*/ REGEXP_REPLACE
REGEXP_REPLACE(value, regexp, replacement) Description
Returns a STRING where all substrings of value that match regular expression regexp are replaced with replacement.
You can use backslashed-escaped digits (\1 to \9) within the replacement argument to insert text matching the corresponding parenthesized group in the regexp pattern. Use \0 to refer to the entire matching text.
To add a backslash in your regular expression, you must first escape it. For example, SELECT REGEXP_REPLACE('abc', 'b(.)', 'X\\1'); returns aXc. You can also use raw strings to remove one layer of escaping, for example SELECT REGEXP_REPLACE('abc', 'b(.)', r'X\1');.
The REGEXP_REPLACE function only replaces non-overlapping matches. For example, replacing ana within banana results in only one replacement, not two.
If the regexp argument isn't a valid regular expression, this function returns an error.
Return type
STRING or BYTES
Examples
SELECT REGEXP_REPLACE('# Heading', r'^# ([a-zA-Z0-9\s]+$)', '<h1>\\1</h1>') AS html /*--------------------------+ | html | +--------------------------+ | <h1>Heading</h1> | +--------------------------*/ REGEXP_SUBSTR
REGEXP_SUBSTR(value, regexp[, position[, occurrence]]) Description
Synonym for REGEXP_EXTRACT.
Return type
STRING or BYTES
Examples
WITH example AS (SELECT 'Hello World Helloo' AS value, 'H?ello+' AS regex, 1 AS position, 1 AS occurrence ) SELECT value, regex, position, occurrence, REGEXP_SUBSTR(value, regex, position, occurrence) AS regexp_value FROM example; /*--------------------+---------+----------+------------+--------------+ | value | regex | position | occurrence | regexp_value | +--------------------+---------+----------+------------+--------------+ | Hello World Helloo | H?ello+ | 1 | 1 | Hello | +--------------------+---------+----------+------------+--------------*/ REPEAT
REPEAT(original_value, repetitions) Description
Returns a STRING or BYTES value that consists of original_value, repeated. The repetitions parameter specifies the number of times to repeat original_value. Returns NULL if either original_value or repetitions are NULL.
This function returns an error if the repetitions value is negative.
Return type
STRING or BYTES
Examples
SELECT REPEAT('abc', 3) AS results /*-----------+ | results | |-----------| | abcabcabc | +-----------*/ SELECT REPEAT('abc', NULL) AS results /*---------+ | results | |---------| | NULL | +---------*/ SELECT REPEAT(NULL, 3) AS results /*---------+ | results | |---------| | NULL | +---------*/ REPLACE
REPLACE(original_value, from_pattern, to_pattern) Description
Replaces all occurrences of from_pattern with to_pattern in original_value. If from_pattern is empty, no replacement is made.
This function supports specifying collation.
Return type
STRING or BYTES
Examples
WITH desserts AS (SELECT 'apple pie' as dessert UNION ALL SELECT 'blackberry pie' as dessert UNION ALL SELECT 'cherry pie' as dessert) SELECT REPLACE (dessert, 'pie', 'cobbler') as example FROM desserts; /*--------------------+ | example | +--------------------+ | apple cobbler | | blackberry cobbler | | cherry cobbler | +--------------------*/ REVERSE
REVERSE(value) Description
Returns the reverse of the input STRING or BYTES.
Return type
STRING or BYTES
Examples
SELECT REVERSE('abc') AS results /*---------+ | results | +---------+ | cba | +---------*/ SELECT FORMAT('%T', REVERSE(b'1a3')) AS results /*---------+ | results | +---------+ | b"3a1" | +---------*/ RIGHT
RIGHT(value, length) Description
Returns a STRING or BYTES value that consists of the specified number of rightmost characters or bytes from value. The length is an INT64 that specifies the length of the returned value. If value is BYTES, length is the number of rightmost bytes to return. If value is STRING, length is the number of rightmost characters to return.
If length is 0, an empty STRING or BYTES value will be returned. If length is negative, an error will be returned. If length exceeds the number of characters or bytes from value, the original value will be returned.
Return type
STRING or BYTES
Examples
SELECT 'apple' AS example, RIGHT('apple', 3) AS right_example /*---------+---------------+ | example | right_example | +---------+---------------+ | apple | ple | +---------+---------------*/ SELECT b'apple' AS example, RIGHT(b'apple', 3) AS right_example -- Note that the result of RIGHT is of type BYTES, displayed as a base64-encoded string. /*----------+---------------+ | example | right_example | +----------+---------------+ | YXBwbGU= | cGxl | +----------+---------------*/ RPAD
RPAD(original_value, return_length[, pattern]) Description
Returns a STRING or BYTES value that consists of original_value appended with pattern. The return_length parameter is an INT64 that specifies the length of the returned value. If original_value is BYTES, return_length is the number of bytes. If original_value is STRING, return_length is the number of characters.
The default value of pattern is a blank space.
Both original_value and pattern must be the same data type.
If return_length is less than or equal to the original_value length, this function returns the original_value value, truncated to the value of return_length. For example, RPAD('hello world', 7); returns 'hello w'.
If original_value, return_length, or pattern is NULL, this function returns NULL.
This function returns an error if:
return_lengthis negativepatternis empty
Return type
STRING or BYTES
Examples
SELECT FORMAT('%T', RPAD('c', 5)) AS results /*---------+ | results | +---------+ | "c " | +---------*/ SELECT RPAD('b', 5, 'a') AS results /*---------+ | results | +---------+ | baaaa | +---------*/ SELECT RPAD('abc', 10, 'ghd') AS results /*------------+ | results | +------------+ | abcghdghdg | +------------*/ SELECT RPAD('abc', 2, 'd') AS results /*---------+ | results | +---------+ | ab | +---------*/ SELECT FORMAT('%T', RPAD(b'abc', 10, b'ghd')) AS results /*---------------+ | results | +---------------+ | b"abcghdghdg" | +---------------*/ RTRIM
RTRIM(value1[, value2]) Description
Identical to TRIM, but only removes trailing characters.
Return type
STRING or BYTES
Examples
SELECT RTRIM('***apple***', '*') AS example /*-----------+ | example | +-----------+ | ***apple | +-----------*/ SELECT RTRIM('applexxz', 'xyz') AS example /*---------+ | example | +---------+ | apple | +---------*/ SAFE_CONVERT_BYTES_TO_STRING
SAFE_CONVERT_BYTES_TO_STRING(value) Description
Converts a sequence of BYTES to a STRING. Any invalid UTF-8 characters are replaced with the Unicode replacement character, U+FFFD.
Return type
STRING
Examples
The following statement returns the Unicode replacement character, �.
SELECT SAFE_CONVERT_BYTES_TO_STRING(b'\xc2') as safe_convert; SOUNDEX
SOUNDEX(value) Description
Returns a STRING that represents the Soundex code for value.
SOUNDEX produces a phonetic representation of a string. It indexes words by sound, as pronounced in English. It's typically used to help determine whether two strings, such as the family names Levine and Lavine, or the words to and too, have similar English-language pronunciation.
The result of the SOUNDEX consists of a letter followed by 3 digits. Non-latin characters are ignored. If the remaining string is empty after removing non-Latin characters, an empty STRING is returned.
Return type
STRING
Examples
SELECT 'Ashcraft' AS value, SOUNDEX('Ashcraft') AS soundex /*----------------------+---------+ | value | soundex | +----------------------+---------+ | Ashcraft | A261 | +----------------------+---------*/ SPLIT
SPLIT(value[, delimiter]) Description
Splits a STRING or BYTES value, using a delimiter. The delimiter argument must be a literal character or sequence of characters. You can't split with a regular expression.
For STRING, the default delimiter is the comma ,.
For BYTES, you must specify a delimiter.
Splitting on an empty delimiter produces an array of UTF-8 characters for STRING values, and an array of BYTES for BYTES values.
Splitting an empty STRING returns an ARRAY with a single empty STRING.
This function supports specifying collation.
Return type
ARRAY<STRING> or ARRAY<BYTES>
Examples
WITH letters AS (SELECT '' as letter_group UNION ALL SELECT 'a' as letter_group UNION ALL SELECT 'b c d' as letter_group) SELECT SPLIT(letter_group, ' ') as example FROM letters; /*----------------------+ | example | +----------------------+ | [] | | [a] | | [b, c, d] | +----------------------*/ STARTS_WITH
STARTS_WITH(value, prefix) Description
Takes two STRING or BYTES values. Returns TRUE if prefix is a prefix of value.
This function supports specifying collation.
Return type
BOOL
Examples
SELECT STARTS_WITH('bar', 'b') AS example /*---------+ | example | +---------+ | True | +---------*/ STRPOS
STRPOS(value, subvalue) Description
Takes two STRING or BYTES values. Returns the 1-based position of the first occurrence of subvalue inside value. Returns 0 if subvalue isn't found.
This function supports specifying collation.
Return type
INT64
Examples
SELECT STRPOS('[email protected]', '@') AS example /*---------+ | example | +---------+ | 4 | +---------*/ SUBSTR
SUBSTR(value, position[, length]) Description
Gets a portion (substring) of the supplied STRING or BYTES value.
The position argument is an integer specifying the starting position of the substring.
- If
positionis1, the substring starts from the first character or byte. - If
positionis0or less than-LENGTH(value),positionis set to1, and the substring starts from the first character or byte. - If
positionis greater than the length ofvalue, the function produces an empty substring. - If
positionis negative, the function counts from the end ofvalue, with-1indicating the last character or byte.
The length argument specifies the maximum number of characters or bytes to return.
- If
lengthisn't specified, the function produces a substring that starts at the specified position and ends at the last character or byte ofvalue. - If
lengthis0, the function produces an empty substring. - If
lengthis negative, the function produces an error. - The returned substring may be shorter than
length, for example, whenlengthexceeds the length ofvalue, or when the starting position of the substring pluslengthis greater than the length ofvalue.
Return type
STRING or BYTES
Examples
SELECT SUBSTR('apple', 2) AS example /*---------+ | example | +---------+ | pple | +---------*/ SELECT SUBSTR('apple', 2, 2) AS example /*---------+ | example | +---------+ | pp | +---------*/ SELECT SUBSTR('apple', -2) AS example /*---------+ | example | +---------+ | le | +---------*/ SELECT SUBSTR('apple', 1, 123) AS example /*---------+ | example | +---------+ | apple | +---------*/ SELECT SUBSTR('apple', 123) AS example /*---------+ | example | +---------+ | | +---------*/ SELECT SUBSTR('apple', 123, 5) AS example /*---------+ | example | +---------+ | | +---------*/ SUBSTRING
SUBSTRING(value, position[, length]) Alias for SUBSTR.
TO_BASE32
TO_BASE32(bytes_expr) Description
Converts a sequence of BYTES into a base32-encoded STRING. To convert a base32-encoded STRING into BYTES, use FROM_BASE32.
Return type
STRING
Example
SELECT TO_BASE32(b'abcde\xFF') AS base32_string; /*------------------+ | base32_string | +------------------+ | MFRGGZDF74====== | +------------------*/ TO_BASE64
TO_BASE64(bytes_expr) Description
Converts a sequence of BYTES into a base64-encoded STRING. To convert a base64-encoded STRING into BYTES, use FROM_BASE64.
There are several base64 encodings in common use that vary in exactly which alphabet of 65 ASCII characters are used to encode the 64 digits and padding. See RFC 4648 for details. This function adds padding and uses the alphabet [A-Za-z0-9+/=].
Return type
STRING
Example
SELECT TO_BASE64(b'\377\340') AS base64_string; /*---------------+ | base64_string | +---------------+ | /+A= | +---------------*/ To work with an encoding using a different base64 alphabet, you might need to compose TO_BASE64 with the REPLACE function. For instance, the base64url url-safe and filename-safe encoding commonly used in web programming uses -_= as the last characters rather than +/=. To encode a base64url-encoded string, replace + and / with - and _ respectively.
SELECT REPLACE(REPLACE(TO_BASE64(b'\377\340'), '+', '-'), '/', '_') as websafe_base64; /*----------------+ | websafe_base64 | +----------------+ | _-A= | +----------------*/ TO_CODE_POINTS
TO_CODE_POINTS(value) Description
Takes a STRING or BYTES value and returns an array of INT64 values that represent code points or extended ASCII character values.
- If
valueis aSTRING, each element in the returned array represents a code point. Each code point falls within the range of [0, 0xD7FF] and [0xE000, 0x10FFFF]. - If
valueisBYTES, each element in the array is an extended ASCII character value in the range of [0, 255].
To convert from an array of code points to a STRING or BYTES, see CODE_POINTS_TO_STRING or CODE_POINTS_TO_BYTES.
Return type
ARRAY<INT64>
Examples
The following examples get the code points for each element in an array of words.
SELECT 'foo' AS word, TO_CODE_POINTS('foo') AS code_points /*---------+------------------------------------+ | word | code_points | +---------+------------------------------------+ | foo | [102, 111, 111] | +---------+------------------------------------*/ SELECT 'bar' AS word, TO_CODE_POINTS('bar') AS code_points /*---------+------------------------------------+ | word | code_points | +---------+------------------------------------+ | bar | [98, 97, 114] | +---------+------------------------------------*/ SELECT 'baz' AS word, TO_CODE_POINTS('baz') AS code_points /*---------+------------------------------------+ | word | code_points | +---------+------------------------------------+ | baz | [98, 97, 122] | +---------+------------------------------------*/ SELECT 'giraffe' AS word, TO_CODE_POINTS('giraffe') AS code_points /*---------+------------------------------------+ | word | code_points | +---------+------------------------------------+ | giraffe | [103, 105, 114, 97, 102, 102, 101] | +---------+------------------------------------*/ SELECT 'llama' AS word, TO_CODE_POINTS('llama') AS code_points /*---------+------------------------------------+ | word | code_points | +---------+------------------------------------+ | llama | [108, 108, 97, 109, 97] | +---------+------------------------------------*/ The following examples convert integer representations of BYTES to their corresponding ASCII character values.
SELECT b'\x66\x6f\x6f' AS bytes_value, TO_CODE_POINTS(b'\x66\x6f\x6f') AS bytes_value_as_integer /*------------------+------------------------+ | bytes_value | bytes_value_as_integer | +------------------+------------------------+ | foo | [102, 111, 111] | +------------------+------------------------*/ SELECT b'\x00\x01\x10\xff' AS bytes_value, TO_CODE_POINTS(b'\x00\x01\x10\xff') AS bytes_value_as_integer /*------------------+------------------------+ | bytes_value | bytes_value_as_integer | +------------------+------------------------+ | \x00\x01\x10\xff | [0, 1, 16, 255] | +------------------+------------------------*/ The following example demonstrates the difference between a BYTES result and a STRING result. Notice that the character Ā is represented as a two-byte Unicode sequence. As a result, the BYTES version of TO_CODE_POINTS returns an array with two elements, while the STRING version returns an array with a single element.
SELECT TO_CODE_POINTS(b'Ā') AS b_result, TO_CODE_POINTS('Ā') AS s_result; /*------------+----------+ | b_result | s_result | +------------+----------+ | [196, 128] | [256] | +------------+----------*/ TO_HEX
TO_HEX(bytes) Description
Converts a sequence of BYTES into a hexadecimal STRING. Converts each byte in the STRING as two hexadecimal characters in the range (0..9, a..f). To convert a hexadecimal-encoded STRING to BYTES, use FROM_HEX.
Return type
STRING
Example
SELECT b'\x00\x01\x02\x03\xAA\xEE\xEF\xFF' AS byte_string, TO_HEX(b'\x00\x01\x02\x03\xAA\xEE\xEF\xFF') AS hex_string /*----------------------------------+------------------+ | byte_string | hex_string | +----------------------------------+------------------+ | \x00\x01\x02\x03\xaa\xee\xef\xff | 00010203aaeeefff | +----------------------------------+------------------*/ TRANSLATE
TRANSLATE(expression, source_characters, target_characters) Description
In expression, replaces each character in source_characters with the corresponding character in target_characters. All inputs must be the same type, either STRING or BYTES.
- Each character in
expressionis translated at most once. - A character in
expressionthat isn't present insource_charactersis left unchanged inexpression. - A character in
source_characterswithout a corresponding character intarget_charactersis omitted from the result. - A duplicate character in
source_charactersresults in an error.
Return type
STRING or BYTES
Examples
SELECT TRANSLATE('This is a cookie', 'sco', 'zku') AS translate /*------------------+ | translate | +------------------+ | Thiz iz a kuukie | +------------------*/ TRIM
TRIM(value_to_trim[, set_of_characters_to_remove]) Description
Takes a STRING or BYTES value to trim.
If the value to trim is a STRING, removes from this value all leading and trailing Unicode code points in set_of_characters_to_remove. The set of code points is optional. If it isn't specified, all whitespace characters are removed from the beginning and end of the value to trim.
If the value to trim is BYTES, removes from this value all leading and trailing bytes in set_of_characters_to_remove. The set of bytes is required.
Return type
STRINGifvalue_to_trimis aSTRINGvalue.BYTESifvalue_to_trimis aBYTESvalue.
Examples
In the following example, all leading and trailing whitespace characters are removed from item because set_of_characters_to_remove isn't specified.
SELECT CONCAT('#', TRIM( ' apple '), '#') AS example /*----------+ | example | +----------+ | #apple# | +----------*/ In the following example, all leading and trailing * characters are removed from 'apple'.
SELECT TRIM('***apple***', '*') AS example /*---------+ | example | +---------+ | apple | +---------*/ In the following example, all leading and trailing x, y, and z characters are removed from 'xzxapplexxy'.
SELECT TRIM('xzxapplexxy', 'xyz') as example /*---------+ | example | +---------+ | apple | +---------*/ In the following example, examine how TRIM interprets characters as Unicode code-points. If your trailing character set contains a combining diacritic mark over a particular letter, TRIM might strip the same diacritic mark from a different letter.
SELECT TRIM('abaW̊', 'Y̊') AS a, TRIM('W̊aba', 'Y̊') AS b, TRIM('abaŪ̊', 'Y̊') AS c, TRIM('Ū̊aba', 'Y̊') AS d /*------+------+------+------+ | a | b | c | d | +------+------+------+------+ | abaW | W̊aba | abaŪ | Ūaba | +------+------+------+------*/ In the following example, all leading and trailing b'n', b'a', b'\xab' bytes are removed from item.
SELECT b'apple', TRIM(b'apple', b'na\xab') AS example -- Note that the result of TRIM is of type BYTES, displayed as a base64-encoded string. /*----------------------+------------------+ | item | example | +----------------------+------------------+ | YXBwbGU= | cHBsZQ== | +----------------------+------------------*/ UNICODE
UNICODE(value) Description
Returns the Unicode code point for the first character in value. Returns 0 if value is empty, or if the resulting Unicode code point is 0.
Return type
INT64
Examples
SELECT UNICODE('âbcd') as A, UNICODE('â') as B, UNICODE('') as C, UNICODE(NULL) as D; /*-------+-------+-------+-------+ | A | B | C | D | +-------+-------+-------+-------+ | 226 | 226 | 0 | NULL | +-------+-------+-------+-------*/ UPPER
UPPER(value) Description
For STRING arguments, returns the original string with all alphabetic characters in uppercase. Mapping between uppercase and lowercase is done according to the Unicode Character Database without taking into account language-specific mappings.
For BYTES arguments, the argument is treated as ASCII text, with all bytes greater than 127 left intact.
Return type
STRING or BYTES
Examples
SELECT UPPER('foo') AS example /*---------+ | example | +---------+ | FOO | +---------*/