Functions Database Functions String functions

String Functions

Note
Since version 3.0.0-beta, the ::is:: functions (e.g. string::is::domain()) now use underscores (e.g. string::is_domain()) to better match the intent of the function and method syntax.

These functions can be used when working with and manipulating text and string values.

Function	Description
`string::capitalize()`	Capitalizes each word of a string
`string::concat()`	Concatenates strings together
`string::contains()`	Checks whether a string contains another string
`string::ends_with()`	Checks whether a string ends with another string
`string::join()`	Joins strings together with a delimiter
`string::len()`	Returns the length of a string
`string::lowercase()`	Converts a string to lowercase
`string::matches()`	Performs a regex match on a string
`string::repeat()`	Repeats a string a number of times
`string::replace()`	Replaces an occurrence of a string with another string
`string::reverse()`	Reverses a string
`string::slice()`	Extracts and returns a section of a string
`string::slug()`	Converts a string into human and URL-friendly string
`string::split()`	Divides a string into an ordered list of substrings
`string::starts_with()`	Checks whether a string starts with another string
`string::trim()`	Removes whitespace from the start and end of a string
`string::uppercase()`	Converts a string to uppercase
`string::words()`	Splits a string into an array of separate words
`string::distance::damerau_levenshtein()`	Returns the Damerau–Levenshtein distance between two strings
`string::distance::normalized_damerau_levenshtein()`	Returns the normalized Damerau–Levenshtein distance between two strings
`string::distance::hamming()`	Returns the Hamming distance between two strings
`string::distance::levenshtein()`	Returns the Levenshtein distance between two strings
`string::distance::normalized_levenshtein()`	Returns the normalized Levenshtein distance between two strings
`string::distance::osa()`	Returns the OSA (Optimal String Alignment) distance between two strings
`string::html::encode()`	Encodes special characters into HTML entities to prevent HTML injection
`string::html::sanitize()`	Sanitizes HTML code to prevent the most dangerous subset of HTML injection
`string::is_alphanum()`	Checks whether a value has only alphanumeric characters
`string::is_alpha()`	Checks whether a value has only alpha characters
`string::is_ascii()`	Checks whether a value has only ascii characters
`string::is_datetime()`	Checks whether a string representation of a date and time matches a specified format
`string::is_domain()`	Checks whether a value is a domain
`string::is_email()`	Checks whether a value is an email
`string::is_hexadecimal()`	Checks whether a value is hexadecimal
`string::is_ip()`	Checks whether a value is an IP address
`string::is_ipv4()`	Checks whether a value is an IP v4 address
`string::is_ipv6()`	Checks whether a value is an IP v6 address
`string::is_latitude()`	Checks whether a value is a latitude value
`string::is_longitude()`	Checks whether a value is a longitude value
`string::is_numeric()`	Checks whether a value has only numeric characters
`string::is_record()`	Checks whether a string is a Record ID, optionally of a certain table
`string::is_semver()`	Checks whether a value matches a semver version
`string::is_ulid()`	Checks whether a string is a ULID
`string::is_url()`	Checks whether a value is a valid URL
`string::is_uuid()`	Checks whether a string is a UUID
`string::semver::compare()`	Performs a comparison between two semver strings
`string::semver::major()`	Extract the major version from a semver string
`string::semver::minor()`	Extract the minor version from a semver string
`string::semver::patch()`	Extract the patch version from a semver string
`string::semver::inc::major()`	Increment the major version of a semver string
`string::semver::inc::minor()`	Increment the minor version of a semver string
`string::semver::inc::patch()`	Increment the patch version of a semver string
`string::semver::set::major()`	Set the major version of a semver string
`string::semver::set::minor()`	Set the minor version of a semver string
`string::semver::set::patch()`	Set the patch version of a semver string
`string::similarity::fuzzy()`	Return the similarity score of fuzzy matching strings
`string::similarity::jaro()`	Returns the Jaro similarity between two strings
`string::similarity::jaro_winkler()`	Return the Jaro-Winkler similarity between two strings

`string::capitalize`

Available since: v3.0.0

The string::capitalize function capitalizes the first letter of each word in a string.

API DEFINITION
string::capitalize(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

string::capitalize("how to cook for forty humans");

-- 'How To Cook For Forty Humans'

`string::concat`

The string::concat function concatenates values together into a single string.

API DEFINITION
string::concat(value, ...) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::concat('this', ' ', 'is', ' ', 'a', ' ', 'test');

-- 'this is a test'

Any values received that are not a string will be stringified before concatenation.

string::concat(true, [], false);
-- ['true[]false']

Note that the stringified inputs are based on their actual computed values, and not the input tokens themselves. Even an expression can be

string::concat(not, actual, values);
-- ['NONENONENONE']

string::concat(CREATE ONLY person:aeon RETURN VALUE id, ' is ', 'cool!');
-- ['person:aeon is cool!']

`string::contains`

The string::contains function checks whether a string contains another string.

API DEFINITION
string::contains(string, $predicate: string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::contains('abcdefg', 'cde');

-- true

`string::ends_with`

Available since: v2.0.0

Note
This function was known as string::endsWith in versions of SurrrealDB before 2.0. The behaviour has not changed.

The string::ends_with function checks whether a string ends with another string.

API DEFINITION
string::ends_with(string, $other: string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::ends_with('some test', 'test');

-- true

`string::join`

The string::join function joins strings or stringified values together with a delimiter.

If you want to join an array of strings use array::join.

API DEFINITION
string::join($delimiter: value, value...) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::join(', ', 'a', 'list', 'of', 'items');

-- "a, list, of, items"

`string::len`

The string::len function returns the length of a given string in characters.

API DEFINITION
string::len(string) -> number

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::len('this is a test');

-- 14

`string::lowercase`

The string::lowercase function converts a string to lowercase.

API DEFINITION
string::lowercase(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::lowercase('THIS IS A TEST');

-- 'this is a test'

`string::matches`

The string::matches function performs a regex match on a string.

API DEFINITION
string::matches(string, $match_with: string|regex) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

[
  string::matches("grey", "gr(a|e)y"), 
  string::matches("gray", "gr(a|e)y")
];

-- [true, true]

The second argument can be either a string or a regex.

LET $input = "grey";
LET $string = "gr(a|e)y";
LET $regex = <regex>"gr(a|e)y";

[type::of($string), type::of($regex)];
-- ['string', 'regex']

[
  string::matches($input, $string),
  string::matches($input, $regex),
];
-- [true, true]

`string::repeat`

The string::repeat function repeats a string a number of times.

API DEFINITION
string::repeat(string, $times: number) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::repeat('test', 3);

-- 'testtesttest'

`string::replace`

The string::replace function replaces an occurrence of a string with another string.

Before 2.3
After 2.3

API DEFINITION
string::replace(string, $from: string, $to: string) -> string

API DEFINITION
string::replace(string, $from: string|regex, $to: string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::replace('this is a test', 'a test', 'awesome');

-- 'this is awesome'

With regexes added as a data type in version 2.3, the second argument can also be a regex instead of a string.

RETURN string::replace('Many languages only use consonants in their writing', <regex>'a|e|i|o|u', '');

Output
'Mny lnggs nly s cnsnnts n thr wrtng'

`string::reverse`

The string::reverse function reverses a string.

API DEFINITION
string::reverse(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::reverse('this is a test');

-- 'tset a si siht'

`string::slice`

The string::slice function extracts and returns a section of a string.

API DEFINITION
string::slice(string, $from: number, $to: number) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::slice('this is a test', 10, 4);

"test"

`string::slug`

The string::slug function converts a string into a human and URL-friendly string.

API DEFINITION
string::slug(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::slug('SurrealDB Cloud has launched!!! #ai_native_database #awesome');

-- 'surrealdb-cloud-has-launched-ai_native_database-awesome'

`string::split`

The string::split function splits a string by a given delimiter.

API DEFINITION
string::split(string, $delimiter: string) -> array

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::split('this, is, a, list', ', ');

-- ['this', 'is', 'a', 'list']

`string::starts_with`

Available since: v2.0.0

Note
This function was known as string::startsWith in versions of SurrrealDB before 2.0. The behaviour has not changed.

The string::starts_with function checks whether a string starts with another string.

API DEFINITION
string::starts_with(string, $predicate: string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::starts_with('some test', 'some');

-- true

`string::trim`

The string::trim function removes whitespace from the start and end of a string.

API DEFINITION
string::trim(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::trim('    this is a test    ');

-- 'this is a test'

`string::uppercase`

The string::uppercase function converts a string to uppercase.

API DEFINITION
string::uppercase(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::uppercase('this is a test');

-- 'THIS IS A TEST'

`string::words`

The string::words function splits a string into an array of separate words.

API DEFINITION
string::words(string) -> array

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::words('this is a test');

-- ['this', 'is', 'a', 'test']

`string::distance::damerau_levenshtein`

Available since: v2.1.0

The string::distance::damerau_levenshtein function returns the Damerau-Levenshtein distance between two strings.

API DEFINITION
string::distance::damerau_levenshtein(string, string) -> int

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 0
string::distance::damerau_levenshtein($first, $same);
-- Returns 7
string::distance::damerau_levenshtein($first, $close);
-- Returns 34
string::distance::damerau_levenshtein($first, $different);
-- Returns 38
string::distance::damerau_levenshtein($first, $short);

`string::distance::normalized_damerau_levenshtein`

Available since: v2.1.0

The string::distance::normalized_damerau_levenshtein function returns the normalized Damerau-Levenshtein distance between two strings. Normalized means that identical strings will return a score of 1, with less similar strings returning lower numbers as the distance grows.

API DEFINITION
string::distance::normalized_damerau_levenshtein(string, string) -> float

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 1f
string::distance::normalized_damerau_levenshtein($first, $same);
-- Returns 0.8409090909090909f
string::distance::normalized_damerau_levenshtein($first, $close);
-- Returns 0.2272727272727273f
string::distance::normalized_damerau_levenshtein($first, $different);
-- Returns 0.13636363636363635f
string::distance::normalized_damerau_levenshtein($first, $short);

`string::distance::hamming`

Available since: v2.1.0

The string::distance::hamming function returns the Hamming distance between two strings of equal length.

API DEFINITION
string::distance::hamming(string, string) -> int

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 0
string::distance::hamming($first, $same);
-- Returns 7
string::distance::hamming($first, $close);
-- Returns 40
string::distance::hamming($first, $different);
-- Error: strings must be of equal length
string::distance::hamming($first, $short);

`string::distance::levenshtein`

Available since: v2.1.0

The string::distance::levenshtein function returns the Levenshtein distance between two strings.

API DEFINITION
string::distance::levenshtein(string, string) -> int

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 0
string::distance::levenshtein($first, $same);
-- Returns 7
string::distance::levenshtein($first, $close);
-- Returns 35
string::distance::levenshtein($first, $different);
-- Returns 38
string::distance::levenshtein($first, $short);

`string::distance::normalized_levenshtein`

Available since: v2.1.0

The string::distance::normalized_levenshtein function returns the normalized Levenshtein distance between two strings. Normalized means that identical strings will return a score of 1, with less similar strings returning lower numbers as the distance grows.

API DEFINITION
string::distance::normalized_levenshtein(string, string) -> float

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 1
string::distance::normalized_levenshtein($first, $same);
-- Returns 0.8409090909090909f
string::distance::normalized_levenshtein($first, $close);
-- Returns 0.20454545454545459f
string::distance::normalized_levenshtein($first, $different);
-- Returns 0.13636363636363635f
string::distance::normalized_levenshtein($first, $short);

`string::distance::osa`

Note
This function was known as string::distance::osa_distance in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

Available since: v2.1.0

The string::distance::osa_distance function returns the OSA (Optimal String Alignment) distance between two strings.

API DEFINITION
string::distance::normalized_levenshtein(string, string) -> int

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 0
string::distance::osa($first, $same);
-- Returns 7
string::distance::osa($first, $close);
-- Returns 34
string::distance::osa($first, $different);
-- Returns 38
string::distance::osa($first, $short);

`string::html::encode`

Available since: v2.0.0

The string::html::encode function encodes special characters into HTML entities to prevent HTML injection. It is recommended to use this function in most cases when retrieving any untrusted content that may be rendered inside of an HTML document. You can learn more about its behavior from the original implementation.

API DEFINITION
string::html::encode(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::html::encode("<h1>Safe Title</h1><script>alert('XSS')</script><p>Safe paragraph. Not safe <span onload='logout()'>event</span>.</p>");

-- '&lt;h1&gt;Safe&#32;Title&lt;&#47;h1&gt;&lt;script&gt;alert(&apos;XSS&apos;)&lt;&#47;script&gt;&lt;p&gt;Safe&#32;paragraph.&#32;Not&#32;safe&#32;&lt;span&#32;onload&#61;&apos;logout()&apos;&gt;event&lt;&#47;span&gt;.&lt;&#47;p&gt;'

`string::html::sanitize`

Available since: v2.0.0

The string::html::sanitize function sanitizes HTML code to prevent the most dangerous subset of HTML injection that can lead to attacks like cross-site scripting, layout breaking or clickjacking. This function will keep any other HTML syntax intact in order to support user-generated content that needs to contain HTML styling. It is only recommended to rely on this function if you want to allow the creators of the content to have some control over its HTML styling. You can learn more about its behavior from the original implementation.

API DEFINITION
string::html::sanitize(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::html::sanitize("<h1>Safe Title</h1><script>alert('XSS')</script><p>Safe paragraph. Not safe <span onload='logout()'>event</span>.</p>");

-- '<h1>Safe Title</h1><p>Safe paragraph. Not safe <span>event</span>.</p>'

`string::is_alphanum`

Note
This function was known as string::is::alphanum in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_alphanum function checks whether a value has only alphanumeric characters.

API DEFINITION
string::is_alphanum(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_alphanum("ABC123");

-- true

`string::is_alpha`

Note
This function was known as string::is::alpha in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_alpha function checks whether a value has only alpha characters.

API DEFINITION
string::is_alpha(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_alpha("ABCDEF");

-- true

`string::is_ascii`

Note
This function was known as string::is::ascii in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_ascii function checks whether a value has only ascii characters.

API DEFINITION
string::is_ascii(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_ascii("ABC123"); -- true
'𓀀'.is_ascii(); -- false

`string::is_datetime`

Note
This function was known as string::is::datetime in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_datetime function checks whether a string representation of a date and time matches either the datetime format or a user-specified format.

API DEFINITION
string::is_datetime(string, $format: option<string>) -> bool

If no second argument is specified, this function will check if a string is a datetime or a format that can be cast into a datetime.

'1970-01-01'.is_datetime();  -- true
'1970-Jan-01'.is_datetime(); -- false

With a second argument, this function will check if a string matches the user-specified format. The output false may be returned in this case even if the input string is a valid datetime.

RETURN string::is_datetime("2015-09-05 23:56:04", "%Y-%m-%d %H:%M:%S");
-- true

RETURN string::is_datetime("1970-01-01", "%Y-%m-%d %H:%M:%S");
-- false

This can be useful when validating datetimes obtained from other sources that do not use the RFC 3339 format.

RETURN string::is_datetime("5sep2024pm012345.6789", "%d%b%Y%p%I%M%S%.f");

Response
true

RETURN string::is_datetime("23:56:00 2015-09-05", "%Y-%m-%d %H:%M");

Response
false

View all format options

`string::is_domain`

Note
This function was known as string::is::domain in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_domain function checks whether a value is a domain.

API DEFINITION
string::is_domain(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_domain("surrealdb.com");

-- true

`string::is_email`

Note
This function was known as string::is::email in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_email function checks whether a value is an email.

API DEFINITION
string::is_email(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_email("info@surrealdb.com");

true

`string::is_hexadecimal`

Note
This function was known as string::is::hexadecimal in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_hexadecimal function checks whether a value is hexadecimal.

API DEFINITION
string::is_hexadecimal(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_hexadecimal("ff009e");

-- true

`string::is_ip`

Note
This function was known as string::is::ip in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

Available since: v2.0.0

The string::is_ip function checks whether a value is an IP address.

API DEFINITION
string::is_ip(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_ip("192.168.0.1");

-- true

`string::is_ipv4`

Note
This function was known as string::is::ipv4 in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

Available since: v2.0.0

The string::is_ipv4 function checks whether a value is an IP v4 address.

API DEFINITION
string::is_ipv4(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_ipv4("192.168.0.1");

-- true

`string::is_ipv6`

Note
This function was known as string::is::ipv6 in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

Available since: v2.0.0

The string::is_ipv6 function checks whether a value is an IP v6 address.

API DEFINITION
string::is_ipv6(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_ipv6("2001:0db8:85a3:0000:0000:8a2e:0370:7334");

-- true

`string::is_latitude`

Note
This function was known as string::is::latitude in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_latitude function checks whether a value is a latitude value.

API DEFINITION
string::is_latitude(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_latitude("-0.118092");

-- true

`string::is_longitude`

Note
This function was known as string::is::longitude in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_longitude function checks whether a value is a longitude value.

API DEFINITION
string::is_longitude(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_longitude("51.509865");

-- true

`string::is_numeric`

Note
This function was known as string::is::numeric in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_numericfunction checks whether a value has only numeric characters.

API DEFINITION
string::is_numeric(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_numeric("1484091748");

-- true

`string::is_semver`

Note
This function was known as string::is::semver in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_semver function checks whether a value matches a semver version.

API DEFINITION
string::is_semver(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_semver("1.0.0");

-- true

`string::is_ulid`

Note
This function was known as string::is::ulid in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_ulid function checks whether a string is a ULID.

API DEFINITION
string::is_ulid(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_ulid("01JCJB3TPQ50XTG32WM088NKJD");

-- true

`string::is_url`

Note
This function was known as string::is::url in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_url function checks whether a value is a valid URL.

API DEFINITION
string::is_url(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_url("https://surrealdb.com");

-- true

`string::is_record`

Note
This function was known as string::is::record in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_record function checks whether a string is a Record ID.

API DEFINITION
string::is_record(string, $table_name: option<string|table>) -> bool

The second argument is optional and can be used to specify the table name that the record ID should belong to. If the table name is provided, the function will check if the record ID belongs to that table only.

RETURN string::is_record("person:test");           -- true
RETURN string::is_record("person:test", "person"); -- true
RETURN string::is_record("person:test", type::table("personn")); -- false
RETURN string::is_record("person:test", "other");  -- false
RETURN string::is_record("not a record id");       -- false

`string::is_uuid`

Note
This function was known as string::is::uuid in versions of SurrrealDB before 3.0.0-beta. The behaviour has not changed.

The string::is_uuid function checks whether a string is a UUID.

API DEFINITION
string::is_uuid(string) -> bool

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::is_uuid("018a6680-bef9-701b-9025-e1754f296a0f");

-- true

`string::semver::compare`

Available since: v1.2.0

The string::semver::compare function performs a comparison on two semver strings and returns a number.

A value of -1 indicates the first version is lower than the second, 0 indicates both versions are equal, and 1 indicates the first version is higher than the second.

API DEFINITION
string::semver::compare(string, $other: string) -> 1|0|-1

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::compare("1.0.0", "1.3.5");
-- Returns -1
RETURN string::semver::compare("1.0.0", "1.0.0");
-- Returns 0
RETURN string::semver::compare("3.0.0-beta.4", "2.6.0");
-- Returns 1

`string::semver::major`

Available since: v1.2.0

The string::semver::major function extracts the major number out of a semver string.

API DEFINITION
string::semver::major(string) -> number

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::major("3.2.6");

-- 3

`string::semver::minor`

Available since: v1.2.0

The string::semver::minor function extracts the minor number out of a semver string.

API DEFINITION
string::semver::minor(string) -> number

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::minor("3.2.6");

-- 2

`string::semver::patch`

Available since: v1.2.0

The string::semver::patch function extracts the patch number out of a semver string.

API DEFINITION
string::semver::patch(string) -> number

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::patch("3.2.6");

-- 6

`string::semver::inc::major`

Available since: v1.2.0

The string::semver::inc::major function increments the major number of a semver string. As a result, the minor and patch numbers are reset to zero.

API DEFINITION
string::semver::inc::major(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::inc::major("1.2.3");

-- '2.0.0'

`string::semver::inc::minor`

Available since: v1.2.0

The string::semver::inc::minor function increments the minor number of a semver string. As a result, the patch number is reset to zero.

API DEFINITION
string::semver::inc::minor(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::inc::minor("1.2.3");

-- '1.3.0'

`string::semver::inc::patch`

Available since: v1.2.0

The string::semver::inc::patch function increments the patch number of a semver string.

API DEFINITION
string::semver::inc::patch(string) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::inc::patch("1.2.3");

-- '1.2.4'

`string::semver::set::major`

Available since: v1.2.0

The string::semver::set::major function sets the major number of a semver string without changing the minor and patch numbers.

API DEFINITION
string::semver::set::major(string, $major: number) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::set::major("1.2.3", 9);

-- '9.2.3'

`string::semver::set::minor`

Available since: v1.2.0

The string::semver::set::minor function sets the minor number of a semver string without changing the major and patch numbers.

API DEFINITION
string::semver::set::minor(string, $minor: number) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::set::minor("1.2.3", 9);

-- '1.9.3'

`string::semver::set::patch`

Available since: v1.2.0

The string::semver::set::patch function sets the patch number of a semver string without changing the major and minor numbers.

API DEFINITION
string::semver::set::patch(string, $patch: number) -> string

The following example shows this function, and its output, when used in a RETURN statement:

RETURN string::semver::set::patch("1.2.3", 9);

-- '1.2.9'

`string::similarity::fuzzy`

API DEFINITION
string::similarity::fuzzy(string, string) -> int

The string::similarity::fuzzy function allows a comparison of similarity to be made. Any value that is greater than 0 is considered a fuzzy match.

-- returns 51
RETURN string::similarity::fuzzy("DB", "DB");
-- returns 47
RETURN string::similarity::fuzzy("DB", "db");

The similarity score is not based on a single score such as 1 to 100, but is built up over the course of the algorithm used to compare one string to another and will be higher for longer strings. As a result, similarity can only be compared from a single string to a number of possible matches, but not multiple strings to a number of possible matches.

While the first two uses of the function in the following example compare identical strings, the longer string returns a much higher fuzzy score.

-- returns 51
RETURN string::similarity::fuzzy("DB", "DB");
-- returns 2997
RETURN string::similarity::fuzzy(
  "SurrealDB Cloud Beta is now live! We are excited to announce that we are inviting users from the waitlist to join. Stay tuned for your invitation!", "SurrealDB Cloud Beta is now live! We are excited to announce that we are inviting users from the waitlist to join. Stay tuned for your invitation!"
);
-- returns 151 despite nowhere close to exact match
RETURN string::similarity::fuzzy(
  "SurrealDB Cloud Beta is now live! We are excited to announce that we are inviting users from the waitlist to join. Stay tuned for your invitation!", "Surreal"
);

A longer example showing a comparison of similarity scores to one another:

LET $original = "SurrealDB";
LET $strings = ["SurralDB", "surrealdb", "DB", "Surreal", "real", "basebase", "eel", "eal"];

FOR $string IN $strings {
    LET $score = string::similarity::fuzzy($original, $string);
    IF $score > 0 {
        CREATE comparison SET of = $original + '\t' + $string,
        score = $score
    };
};

SELECT of, score FROM comparison ORDER BY score DESC;

Response
[
	{
		of: 'SurrealDB	surrealdb',
		score: 187
	},
	{
		of: 'SurrealDB	SurralDB',
		score: 165
	},
	{
		of: 'SurrealDB	Surreal',
		score: 151
	},
	{
		of: 'SurrealDB	real',
		score: 75
	},
	{
		of: 'SurrealDB	eal',
		score: 55
	},
	{
		of: 'SurrealDB	DB',
		score: 41
	}
]

`string::similarity::jaro`

Available since: v2.1.0

The string::similarity::jaro function returns the Jaro similarity between two strings. Two strings that are identical have a score of 1, while less similar strings will have lower scores as the distance between them increases.

API DEFINITION
string::similarity::jaro(string, string) -> float

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 1
string::similarity::jaro($first, $same);
-- Returns 0.8218673218673219f
string::similarity::jaro($first, $close);
-- Returns 0.6266233766233765f
string::similarity::jaro($first, $different);
-- Returns 0.4379509379509379f
string::similarity::jaro($first, $short);

`string::similarity::jaro_winkler`

Available since: v2.1.0

The string::similarity::jaro_winkler function returns the Jaro-Winkler similarity between two strings. Two strings that are identical have a score of 1, while less similar strings will have lower scores as the distance between them increases.

API DEFINITION
string::similarity::jaro_winkler(string, string) -> float

The following examples shows this function, and its output in comparison with a number of strings.

LET $first     = "In a hole in the ground there lived a hobbit";
LET $same      = "In a hole in the ground there lived a hobbit";
LET $close     = "In a hole in the GROUND there lived a Hobbit";
LET $different = "A narrow passage holds four hidden treasures";
LET $short     = "Hi I'm Brian";

-- Returns 0
string::similarity::jaro_winkler($first, $same);
-- Returns 0.8931203931203932f
string::similarity::jaro_winkler($first, $close);
-- Returns 0.6266233766233765f
string::similarity::jaro_winkler($first, $different);
-- Returns 0.4379509379509379f
string::similarity::jaro_winkler($first, $short);

Method chaining

Available since: v2.0.0

Method chaining allows functions to be called using the . dot operator on a value of a certain type instead of the full path of the function followed by the value.

-- Traditional syntax
string::is_alphanum("MyStrongPassword123");

-- Method chaining syntax
"MyStrongPassword123".is_alphanum();

Response
true

This is particularly useful for readability when a function is called multiple times.

-- Traditional syntax
string::concat(
  string::uppercase(
    string::replace(
      string::replace("I'll send you a check for the catalog", "ck", "que")
    , "og", "ogue")
  )
, "!!!!");

-- Method chaining syntax
"I'll send you a check for the catalog"
  .replace("ck", "que")
  .replace("og", "ogue")
  .uppercase()
  .concat("!!!!");

Response
"I'LL SEND YOU A CHEQUE FOR THE CATALOGUE!!!!"

On this page

Was this page helpful?

What did you like?

What went wrong?