String Functions

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

string::concat

The string::concat function concatenates strings together.

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

string::contains

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

API DEFINITION
string::contains(string, 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, 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 together with a delimiter.

API DEFINITION
string::join(string, string...) -> 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.

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, string) -> bool

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

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

[ true, true ]

string::repeat

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

API DEFINITION
string::repeat(string, 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.

API DEFINITION
string::replace(string, string, 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"

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, number, 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 has launched #database #awesome');

"surrealdb-has-launched-database-awesome"

string::split

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

API DEFINITION
string::split(string, 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, 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::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

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

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

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

string::is::datetime

The string::is::datetime function checks whether a string representation of a date and time matches a specified format.

API DEFINITION
string::is::datetime(string, string) -> bool

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

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

Response
true

This can be useful when validating datetimes obtained from other sources that do not use the ISO 8601 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

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

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

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

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

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

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

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

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

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

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::url

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

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

API DEFINITION
string::is::record(string, option<string | table>) -> bool

Note

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.

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

RETURN string::is::record("person:test");           -- true
RETURN string::is::record("person:test", "person"); -- true
RETURN string::is::record("person:test", "other");  -- false
RETURN string::is::record("not a record id");       -- false

string::is::uuid

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, string) -> number

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");

-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, 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, 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, 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

While the ~ operator is a quick go-to to see if two strings are a fuzzy match, it returns a boolean that does not indicate relative similarity.

RETURN "SurrealDB" ~ "db";
-- true
RETURN "SurrealDB" ~ "surrealdb"
-- true

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(
  "Surreal 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 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(
  "Surreal 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
	}
]

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!!!!'