String Functions
| Name | Description |
BYTE_LENGTH
|
Returns the number of BYTES
in a STRING
or BYTES
value |
CHAR_LENGTH
|
Returns the number of unicode characters in a STRING
value |
STARTS_WITH
|
Returns TRUE
if a STRING
begins with a given prefix |
ENDS_WITH
|
Returns TRUE
if a STRING
ends with a given postfix |
LIKE
|
Returns TRUE
if a STRING
matches a pattern |
REGEX_CONTAINS
|
Returns TRUE
if a value is a partial or full match for a regular expression |
REGEX_MATCH
|
Returns TRUE
if any part of a value matches a regular expression |
STRING_CONCAT
|
Concatenates multiple STRING
into a STRING
|
STRING_CONTAINS
|
Returns TRUE
if a value contains a STRING
|
TO_UPPER
|
Converts a STRING
or BYTES
value to uppercase. |
TO_LOWER
|
Converts a STRING
or BYTES
value to lowercase. |
SUBSTRING
|
Gets a substring of a STRING
or BYTES
value. |
STRING_REVERSE
|
Reverses a STRING
or BYTES
value. |
TRIM
|
Trims leading and trailing characters from a STRING
or BYTES
value. |
SPLIT
|
Splits a STRING
or BYTES
value into an array. |
BYTE_LENGTH
Syntax:
byte_length[T <: STRING | BYTES](value: T) -> INT64
Description:
Returns the number of BYTES
in a STRING
or BYTES
value.
Examples:
| value | byte_length(value)
|
|---|---|
| "abc" | 3 |
| "xyzabc" | 6 |
| b"abc" | 3 |
Node.js
const result = await db . pipeline () . collection ( "books" ) . select ( field ( "title" ). byteLength (). as ( "titleByteLength" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "title" ). byteLength (). as ( "titleByteLength" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "title" ). byteLength (). as ( "titleByteLength" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). byteLength (). alias ( "titleByteLength" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). byteLength (). alias ( "titleByteLength" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "title" ) . byte_length () . as_ ( "titleByteLength" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( byteLength ( field ( "title" )). as ( "titleByteLength" )) . execute () . get ();
CHAR_LENGTH
Syntax:
char_length(value: STRING) -> INT64
Description:
Returns the number of unicode code points in STRING
value.
Examples:
| value | char_length(value)
|
|---|---|
| "abc" | 3 |
| "hello" | 5 |
| "world" | 5 |
Node.js
const result = await db . pipeline () . collection ( "books" ) . select ( field ( "title" ). charLength (). as ( "titleCharLength" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "title" ). charLength (). as ( "titleCharLength" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "title" ). charLength (). as ( "titleCharLength" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). charLength (). alias ( "titleCharLength" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). charLength (). alias ( "titleCharLength" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "title" ) . char_length () . as_ ( "titleCharLength" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( charLength ( field ( "title" )). as ( "titleCharLength" )) . execute () . get ();
STARTS_WITH
Syntax:
starts_with(value: STRING, prefix: STRING) -> BOOLEAN
Description:
Returns TRUE
if value
begins with prefix
.
Examples:
| value | prefix | starts_with(value, prefix)
|
|---|---|---|
|
"abc"
|
"a" | true |
|
"abc"
|
"b" | false |
|
"abc"
|
"" | true |
Node.js
const result = await db . pipeline () . collection ( "books" ) . select ( field ( "title" ). startsWith ( "The" ) . as ( "needsSpecialAlphabeticalSort" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "title" ). startsWith ( "The" ) . as ( "needsSpecialAlphabeticalSort" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "title" ). startsWith ( "The" ) . as ( "needsSpecialAlphabeticalSort" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). startsWith ( "The" ) . alias ( "needsSpecialAlphabeticalSort" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). startsWith ( "The" ) . alias ( "needsSpecialAlphabeticalSort" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "title" ) . starts_with ( "The" ) . as_ ( "needsSpecialAlphabeticalSort" ) ) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( startsWith ( field ( "title" ), "The" ). as ( "needsSpecialAlphabeticalSort" )) . execute () . get ();
ENDS_WITH
Syntax:
ends_with(value: STRING, postfix: STRING) -> BOOLEAN
Description:
Returns TRUE
if value
ends with postfix
.
Examples:
| value | postfix | ends_with(value, postfix)
|
|---|---|---|
|
"abc"
|
"c" | true |
|
"abc"
|
"b" | false |
|
"abc"
|
"" | true |
Node.js
const result = await db . pipeline () . collection ( "inventory/devices/laptops" ) . select ( field ( "name" ). endsWith ( "16 inch" ) . as ( "16InLaptops" ) ) . execute ();
Swift
let result = try await db . pipeline () . collection ( "inventory/devices/laptops" ) . select ([ Field ( "name" ). endsWith ( "16 inch" ) . as ( "16InLaptops" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "inventory/devices/laptops" ) . select ( field ( "name" ). endsWith ( "16 inch" ) . alias ( "16InLaptops" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "inventory/devices/laptops" ) . select ( field ( "name" ). endsWith ( "16 inch" ) . alias ( "16InLaptops" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "inventory/devices/laptops" ) . select ( Field . of ( "name" ) . ends_with ( "16 inch" ) . as_ ( "16InLaptops" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "inventory/devices/laptops" ) . select ( endsWith ( field ( "name" ), "16 inch" ). as ( "16InLaptops" )) . execute () . get ();
LIKE
Syntax:
like(value: STRING, pattern: STRING) -> BOOLEAN
Description:
Returns TRUE
if value
matches pattern
.
Examples:
| value | pattern | like(value, pattern)
|
|---|---|---|
|
"Firestore"
|
"Fire%" | true |
|
"Firestore"
|
"%store" | true |
|
"Datastore"
|
"Data_tore" | true |
|
"100%"
|
"100\%" | true |
Node.js
const result = await db . pipeline () . collection ( "books" ) . select ( field ( "genre" ). like ( "%Fiction" ) . as ( "anyFiction" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "genre" ). like ( "%Fiction" ) . as ( "anyFiction" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "genre" ). like ( "%Fiction" ) . as ( "anyFiction" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "genre" ). like ( "%Fiction" ) . alias ( "anyFiction" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "genre" ). like ( "%Fiction" ) . alias ( "anyFiction" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "genre" ) . like ( " %F iction" ) . as_ ( "anyFiction" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( like ( field ( "genre" ), "%Fiction" ). as ( "anyFiction" )) . execute () . get ();
REGEX_CONTAINS
Syntax:
regex_contains(value: STRING, pattern: STRING) -> BOOLEAN
Description:
Returns TRUE
if some part of value
matches pattern
. If pattern
is not a valid regular expression, this function returns an error
.
Regular expressions follow the syntax of the re2 library.
Examples:
| value | pattern | regex_contains(value, pattern)
|
|---|---|---|
|
"Firestore"
|
"Fire" | true |
|
"Firestore"
|
"store$" | true |
|
"Firestore"
|
"data" | false |
Node.js
const result = await db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexContains ( "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreRelated" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexContains ( "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreRelated" ) ) );
Swift
let result = try await db . pipeline () . collection ( "documents" ) . select ([ Field ( "title" ). regexContains ( "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreRelated" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexContains ( "Firestore (Enterprise|Standard)" ) . alias ( "isFirestoreRelated" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexContains ( "Firestore (Enterprise|Standard)" ) . alias ( "isFirestoreRelated" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "documents" ) . select ( Field . of ( "title" ) . regex_contains ( "Firestore (Enterprise|Standard)" ) . as_ ( "isFirestoreRelated" ) ) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "documents" ) . select ( regexContains ( field ( "title" ), "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreRelated" )) . execute () . get ();
REGEX_MATCH
Syntax:
regex_match(value: STRING, pattern: STRING) -> BOOLEAN
Description:
Returns TRUE
if value
fully matches pattern
. If pattern
is not a valid regular expression, this function returns an error
.
Regular expressions follow the syntax of the re2 library.
Examples:
| value | pattern | regex_match(value, pattern)
|
|---|---|---|
|
"Firestore"
|
"F.*store" | true |
|
"Firestore"
|
"Fire" | false |
|
"Firestore"
|
"^F.*e$" | true |
Node.js
const result = await db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexMatch ( "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreExactly" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexMatch ( "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreExactly" ) ) );
Swift
let result = try await db . pipeline () . collection ( "documents" ) . select ([ Field ( "title" ). regexMatch ( "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreExactly" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexMatch ( "Firestore (Enterprise|Standard)" ) . alias ( "isFirestoreExactly" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "documents" ) . select ( field ( "title" ). regexMatch ( "Firestore (Enterprise|Standard)" ) . alias ( "isFirestoreExactly" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "documents" ) . select ( Field . of ( "title" ) . regex_match ( "Firestore (Enterprise|Standard)" ) . as_ ( "isFirestoreExactly" ) ) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "documents" ) . select ( regexMatch ( field ( "title" ), "Firestore (Enterprise|Standard)" ) . as ( "isFirestoreExactly" )) . execute () . get ();
STRING_CONCAT
Syntax:
string_concat(values: STRING...) -> STRING
Description:
Concatenates two or more STRING
values into a single result.
Examples:
| arguments | string_concat(values...)
|
|---|---|
()
|
error |
("a")
|
"a" |
("abc", "def")
|
"abcdef" |
("a", "", "c")
|
"ac" |
Node.js
const result = await db . pipeline () . collection ( "books" ) . select ( field ( "title" ). stringConcat ( " by " , field ( "author" )) . as ( "fullyQualifiedTitle" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "title" ). stringConcat ( " by " , field ( "author" )) . as ( "fullyQualifiedTitle" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "title" ). concat ([ " by " , Field ( "author" )]) . as ( "fullyQualifiedTitle" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). concat ( " by " , field ( "author" )) . alias ( "fullyQualifiedTitle" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "title" ). concat ( " by " , field ( "author" )) . alias ( "fullyQualifiedTitle" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "title" ) . concat ( " by " , Field . of ( "author" )) . as_ ( "fullyQualifiedTitle" ) ) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( stringConcat ( field ( "title" ), " by " , field ( "author" )). as ( "fullyQualifiedTitle" )) . execute () . get ();
STRING_CONTAINS
Syntax:
string_contains(value: STRING, substring: STRING) -> BOOLEAN
Description:
Checks if value
contains the literal String substring
.
Examples:
| value | substring | string_contains(value, substring)
|
|---|---|---|
|
"abc"
|
"b" | true |
|
"abc"
|
"d" | false |
|
"abc"
|
"" | true |
|
"a.c"
|
"." | true |
|
"☃☃☃"
|
"☃" | true |
Node.js
const result = await db . pipeline () . collection ( "articles" ) . select ( field ( "body" ). stringContains ( "Firestore" ) . as ( "isFirestoreRelated" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "articles" ) . select ( field ( "body" ). stringContains ( "Firestore" ) . as ( "isFirestoreRelated" ) ) );
Swift
let result = try await db . pipeline () . collection ( "articles" ) . select ([ Field ( "body" ). stringContains ( "Firestore" ) . as ( "isFirestoreRelated" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "articles" ) . select ( field ( "body" ). stringContains ( "Firestore" ) . alias ( "isFirestoreRelated" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "articles" ) . select ( field ( "body" ). stringContains ( "Firestore" ) . alias ( "isFirestoreRelated" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "articles" ) . select ( Field . of ( "body" ) . string_contains ( "Firestore" ) . as_ ( "isFirestoreRelated" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "articles" ) . select ( stringContains ( field ( "body" ), "Firestore" ). as ( "isFirestoreRelated" )) . execute () . get ();
TO_UPPER
Syntax:
to_upper[T <: STRING | BYTES](value: T) -> T
Description:
Converts a STRING
or BYTES
value to uppercase.
If a byte or char does not correspond to a UTF-8 lowercase alphabetic character, it is passed through unchanged.
Examples:
| value | to_upper(value)
|
|---|---|
| "abc" | "ABC" |
| "AbC" | "ABC" |
| b"abc" | b"ABC" |
| b"a1c" | b"A1C" |
Node.js
const result = await db . pipeline () . collection ( "authors" ) . select ( field ( "name" ). toUpper () . as ( "uppercaseName" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "authors" ) . select ( field ( "name" ). toUpper () . as ( "uppercaseName" ) ) );
Swift
let result = try await db . pipeline () . collection ( "authors" ) . select ([ Field ( "name" ). toUpper () . as ( "uppercaseName" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "authors" ) . select ( field ( "name" ). toUpper () . alias ( "uppercaseName" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "authors" ) . select ( field ( "name" ). toUpper () . alias ( "uppercaseName" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "authors" ) . select ( Field . of ( "name" ) . to_upper () . as_ ( "uppercaseName" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "authors" ) . select ( toUpper ( field ( "name" )). as ( "uppercaseName" )) . execute () . get ();
TO_LOWER
Syntax:
to_lower[T <: STRING | BYTES](value: T) -> T
Description:
Converts a STRING
or BYTES
value to lowercase.
If a byte or char does not correspond to a UTF-8 uppercase alphabetic character, it is passed through unchanged.
Examples:
| value | to_lower(value)
|
|---|---|
| "ABC" | "abc" |
| "AbC" | "abc" |
| "A1C" | "a1c" |
| b"ABC" | b"abc" |
Node.js
const result = await db . pipeline () . collection ( "authors" ) . select ( field ( "genre" ). toLower (). equal ( "fantasy" ) . as ( "isFantasy" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "authors" ) . select ( field ( "genre" ). toLower (). equal ( "fantasy" ) . as ( "isFantasy" ) ) );
Swift
let result = try await db . pipeline () . collection ( "authors" ) . select ([ Field ( "genre" ). toLower (). equal ( "fantasy" ) . as ( "isFantasy" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "authors" ) . select ( field ( "genre" ). toLower (). equal ( "fantasy" ) . alias ( "isFantasy" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "authors" ) . select ( field ( "genre" ). toLower (). equal ( "fantasy" ) . alias ( "isFantasy" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "authors" ) . select ( Field . of ( "genre" ) . to_lower () . equal ( "fantasy" ) . as_ ( "isFantasy" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "authors" ) . select ( equal ( toLower ( field ( "genre" )), "fantasy" ). as ( "isFantasy" )) . execute () . get ();
SUBSTRING
Syntax:
substring[T <: STRING | BYTES](input: T, position: INT64) -> T
substring[T <: STRING | BYTES](input: T, position: INT64, length: INT64) -> T
Description:
Returns a substring of input
starting at position
(zero-based index) and
including up to length
entries. If no length
is provided, returns the substring
from position
to the end of the input
.
-
If
inputis aSTRINGvalue,positionandlengthare measured in unicode code points. If it is aBYTESvalue, they are measured in bytes. -
If
positionis greater than the length of theinput, an empty substring is returned. Ifpositionpluslengthis greater than the length ofinput, the substring is truncated to the end ofinput. -
If
positionis negative, the position is taken from the end of the input. If the negativepositionis greater than the size of the input, the position is set to zero.lengthmust be non-negative.
Examples:
When length
is not provided:
| input | position | substring(input, position)
|
|---|---|---|
|
"abc"
|
0 | "abc" |
|
"abc"
|
1 | "bc" |
|
"abc"
|
3 | "" |
|
"abc"
|
-1 | "c" |
|
b"abc"
|
1 | b"bc" |
When length
is provided:
| input | position | length | substring(input, position, length)
|
|---|---|---|---|
|
"abc"
|
0 | 1 | "a" |
|
"abc"
|
1 | 2 | "bc" |
|
"abc"
|
-1 | 1 | "c" |
|
b"abc"
|
0 | 1 | b"a" |
Node.js
const result = await db . pipeline () . collection ( "books" ) . where ( field ( "title" ). startsWith ( "The " )) . select ( field ( "title" ). substring ( 4 ) . as ( "titleWithoutLeadingThe" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . where ( field ( "title" ). startsWith ( "The " )) . select ( field ( "title" ). substring ( 4 ) . as ( "titleWithoutLeadingThe" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . where ( Field ( "title" ). startsWith ( "The " )) . select ([ Field ( "title" ). substring ( position : 4 ) . as ( "titleWithoutLeadingThe" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . where ( field ( "title" ). startsWith ( "The " )) . select ( field ( "title" ) . substring ( constant ( 4 ), field ( "title" ). charLength (). subtract ( 4 )) . alias ( "titleWithoutLeadingThe" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . where ( field ( "title" ). startsWith ( "The " )) . select ( field ( "title" ). substring ( constant ( 4 ), field ( "title" ). charLength (). subtract ( 4 )) . alias ( "titleWithoutLeadingThe" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . where ( Field . of ( "title" ) . starts_with ( "The " )) . select ( Field . of ( "title" ) . substring ( 4 ) . as_ ( "titleWithoutLeadingThe" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . where ( startsWith ( field ( "title" ), "The " )) . select ( substring ( field ( "title" ), constant ( 4 ), field ( "title" ). charLength ()) . as ( "titleWithoutLeadingThe" )) . execute () . get ();
STRING_REVERSE
Syntax:
string_reverse[T <: STRING | BYTES](input: T) -> T
Description:
Returns the supplied input in reverse order.
Characters are delineated by Unicode code points when the input is a STRING
, and bytes when the input is a BYTES
value.
Examples:
| input | string_reverse(input)
|
|---|---|
| "abc" | "cba" |
| "a🌹b" | "b🌹a" |
| "hello" | "olleh" |
| b"abc" | b"cba" |
Node.js
const result = await db . pipeline () . collection ( "books" ) . select ( field ( "name" ). reverse (). as ( "reversedName" ) ) . execute ();
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "name" ). reverse (). as ( "reversedName" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "name" ). reverse (). as ( "reversedName" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "name" ). reverse (). alias ( "reversedName" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "name" ). reverse (). alias ( "reversedName" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "name" ) . string_reverse () . as_ ( "reversedName" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( reverse ( field ( "name" )). as ( "reversedName" )) . execute () . get ();
TRIM
Syntax:
trim[T <: STRING | BYTES](input: T, values_to_trim: T) -> T
trim[T <: STRING | BYTES](input: T) -> T
Description:
Trims a specified set of BYTES
or CHARS
from the beginning and end of the
supplied input
.
- If no
values_to_trimare provided, trims whitespace characters.
Examples:
When values_to_trim
is not provided:
| input | trim(input)
|
|---|---|
| " foo " | "foo" |
| b" foo " | b"foo" |
| "foo" | "foo" |
| "" | "" |
| " " | "" |
| "\t foo \n" | "foo" |
| b"\t foo \n" | b"foo" |
| "\r\f\v foo \r\f\v" | "foo" |
| b"\r\f\v foo \r\f\v" | b"foo" |
When values_to_trim
is provided:
| input | values_to_trim | trim(input, values_to_trim)
|
|---|---|---|
|
"abcbfooaacb"
|
"abc" | "foo" |
|
"abcdaabadbac"
|
"abc" | "daabad" |
|
b"C1C2C3"
|
b"C1" | b"C2C3" |
|
b"C1C2"
|
"foo" | error |
|
"foo"
|
b"C1" | error |
Web
const result = await execute ( db . pipeline () . collection ( "books" ) . select ( field ( "name" ). trim (). as ( "whitespaceTrimmedName" ) ) );
Swift
let result = try await db . pipeline () . collection ( "books" ) . select ([ Field ( "name" ). trim ( " \n\t " ). as ( "whitespaceTrimmedName" ) ]) . execute ()
Kotlin
val result = db . pipeline () . collection ( "books" ) . select ( field ( "name" ). trim (). alias ( "whitespaceTrimmedName" ) ) . execute ()
Java
Task<Pipeline . Snapshot > result = db . pipeline () . collection ( "books" ) . select ( field ( "name" ). trim (). alias ( "whitespaceTrimmedName" ) ) . execute ();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field result = ( client . pipeline () . collection ( "books" ) . select ( Field . of ( "name" ) . trim () . as_ ( "whitespaceTrimmedName" )) . execute () )
Java
Pipeline . Snapshot result = firestore . pipeline () . collection ( "books" ) . select ( trim ( field ( "name" )). as ( "whitespaceTrimmedName" )) . execute () . get ();
SPLIT
Syntax:
split(input: STRING) -> ARRAY<STRING>
split[T <: STRING | BYTES](input: T, delimiter: T) -> ARRAY<T>
Description:
Splits a STRING
or BYTES
value, using a delimiter.
-
For
STRINGthe default delimiter is the comma,. The delimiter is treated as a single string. -
For
BYTES, you must specify a delimiter. -
Splitting on an empty delimiter produces an array of Unicode codepoints for
STRINGvalues, and an array ofBYTESforBYTESvalues. -
Splitting an empty
STRINGreturns anARRAYwith a single emptySTRING.
Examples:
When delimiter
is not provided:
| input | split(input)
|
|---|---|
| "foo,bar,foo" | ["foo", "bar", "foo"] |
| "foo" | ["foo"] |
| ",foo," | ["", "foo", ""] |
| "" | [""] |
| b"C120C2C4" | error |
When delimiter
is provided:
| input | delimiter | split(input, delimiter)
|
|---|---|---|
|
"foo bar foo"
|
" " | ["foo", "bar", "foo"] |
|
"foo bar foo"
|
"z" | ["foo bar foo"] |
|
"abc"
|
"" | ["a", "b", "c"] |
|
b"C1,C2,C4"
|
b"," | [b"C1", b"C2", b"C4"] |
|
b"ABC"
|
b"" | [b"A", b"B", b"C"] |
|
"foo"
|
b"C1" | error |
