String functions
For string processing, AQL offers the following functions:
CHAR_LENGTH()
CHAR_LENGTH(str) → length
Return the number of characters in str
(not byte length).
Input | Length |
---|---|
String | Number of Unicode characters |
Number | Number of Unicode characters that represent the number |
Array | Number of Unicode characters from the resulting stringification |
Object | Number of Unicode characters from the resulting stringification |
true | 4 |
false | 5 |
null | 0 |
- str (string): a string. If a number is passed, it will be casted to string first.
- returns length (number): the character length of
str
(not byte length)
Examples
RETURN CHAR_LENGTH("foo")
[
3
]
CONCAT()
CONCAT(value1, value2, ... valueN) → str
Concatenate the values passed as value1
to valueN
.
- values (any, repeatable): elements of arbitrary type (at least 1)
- returns str (string): a concatenation of the elements.
null
values are ignored. Array and object values are JSON-encoded in their entirety.
Examples
RETURN CONCAT("foo", "bar", "baz")
[
"foobarbaz"
]
RETURN CONCAT(1, 2, 3)
[
"123"
]
RETURN CONCAT(null, false, 0, true, "")
[
"false0true"
]
RETURN CONCAT([5, 6], {foo: "bar"})
[
"[5,6]{\"foo\":\"bar\"}"
]
CONCAT(anyArray) → str
If a single array is passed to CONCAT()
, its members are concatenated.
- anyArray (array): array with elements of arbitrary type
- returns str (string): a concatenation of the array elements.
null
values are ignored. Array and object values are JSON-encoded in their entirety.
RETURN CONCAT( [ "foo", "bar", "baz" ] )
[
"foobarbaz"
]
RETURN CONCAT( [1, 2, 3] )
[
"123"
]
RETURN CONCAT( [null, false, 0, true, ""] )
[
"false0true"
]
RETURN CONCAT( [[5, 6], {foo: "bar"}] )
[
"[5,6]{\"foo\":\"bar\"}"
]
CONCAT_SEPARATOR()
CONCAT_SEPARATOR(separator, value1, value2, ... valueN) → joinedString
Concatenate the strings passed as arguments value1
to valueN
using the
separator string.
- separator (string): an arbitrary separator string
- values (string|array, repeatable): strings or arrays of strings as multiple arguments (at least 1)
- returns joinedString (string): a concatenated string of the elements, using
separator
as separator string.null
values are ignored. Array and object values are JSON-encoded in their entirety.
Examples
RETURN CONCAT_SEPARATOR(", ", "foo", "bar", "baz")
[
"foo, bar, baz"
]
RETURN CONCAT_SEPARATOR(", ", 1, 2, 3)
[
"1, 2, 3"
]
RETURN CONCAT_SEPARATOR(", ", null, false, 0, true, "")
[
"false, 0, true, "
]
RETURN CONCAT_SEPARATOR(", ", [5, 6], {foo: "bar"})
[
"[5,6], {\"foo\":\"bar\"}"
]
CONCAT_SEPARATOR(separator, anyArray) → joinedString
If a single array is passed as second argument to CONCAT_SEPARATOR()
, its
members are concatenated.
- separator (string): an arbitrary separator string
- anyArray (array): array with elements of arbitrary type
- returns joinedString (string): a concatenated string of the elements, using
separator
as separator string.null
values are ignored. Array and object values are JSON-encoded in their entirety.
RETURN CONCAT_SEPARATOR(", ", ["foo", "bar", "baz"])
[
"foo, bar, baz"
]
RETURN CONCAT_SEPARATOR(", ", [1, 2, 3])
[
"1, 2, 3"
]
RETURN CONCAT_SEPARATOR(", ", [null, false, 0, true, ""])
[
"false, 0, true, "
]
RETURN CONCAT_SEPARATOR(", ", [[5, 6], {foo: "bar"}])
[
"[5,6], {\"foo\":\"bar\"}"
]
CONTAINS()
CONTAINS(text, search, returnIndex) → match
Check whether the string search
is contained in the string text
.
The string matching performed by CONTAINS()
is case-sensitive.
To determine if or at which position a value is included in an array, see the POSITION() array function.
- text (string): the haystack
- search (string): the needle
- returnIndex (bool, optional): if set to
true
, the character position of the match is returned instead of a boolean. The default isfalse
. - returns match (bool|number): by default,
true
is returned ifsearch
is contained intext
, andfalse
otherwise. WithreturnIndex
set totrue
, the position of the first occurrence ofsearch
withintext
is returned (starting at offset 0), or-1
if it is not contained.
Examples
RETURN CONTAINS("foobarbaz", "bar")
[
true
]
RETURN CONTAINS("foobarbaz", "horse")
[
false
]
RETURN CONTAINS("foobarbaz", "bar", true)
[
3
]
RETURN CONTAINS("foobarbaz", "horse", true)
[
-1
]
COUNT()
This is an alias for LENGTH().
CRC32()
CRC32(text) → hash
Calculate the CRC32 checksum for text
and return it in a hexadecimal
string representation. The polynomial used is 0x1EDC6F41
. The initial
value used is 0xFFFFFFFF
, and the final XOR value is also 0xFFFFFFFF
.
- text (string): a string
- returns hash (string): CRC32 checksum as hex string
Examples
RETURN CRC32("foobar")
[
"D5F5C7F"
]
ENCODE_URI_COMPONENT()
ENCODE_URI_COMPONENT(value) → encodedString
Return the URI component-encoded string of value
.
- value (string): a string
- returns encodedString (string): the URI component-encoded
value
Examples
RETURN ENCODE_URI_COMPONENT("fünf %")
[
"f%C3%BCnf%20%25"
]
FIND_FIRST()
FIND_FIRST(text, search, start, end) → position
Return the position of the first occurrence of the string search
inside the
string text
. Positions start at 0.
- text (string): the haystack
- search (string): the needle
- start (number, optional): limit the search to a subset of the text,
beginning at
start
- end (number, optional): limit the search to a subset of the text,
ending at
end
- returns position (number): the character position of the match. If
search
is not contained intext
, -1 is returned. Ifsearch
is empty,start
is returned.
Examples
RETURN FIND_FIRST("foobarbaz", "ba")
[
3
]
RETURN FIND_FIRST("foobarbaz", "ba", 4)
[
6
]
RETURN FIND_FIRST("foobarbaz", "ba", 0, 3)
[
-1
]
FIND_LAST()
FIND_LAST(text, search, start, end) → position
Return the position of the last occurrence of the string search
inside the
string text
. Positions start at 0.
- text (string): the haystack
- search (string): the needle
- start (number, optional): limit the search to a subset of the text, beginning at start
- end (number, optional): limit the search to a subset of the text, ending at end
- returns position (number): the character position of the match. If
search
is not contained intext
, -1 is returned. Ifsearch
is empty, the string length is returned, orend
+ 1.
Examples
RETURN FIND_LAST("foobarbaz", "ba")
[
6
]
RETURN FIND_LAST("foobarbaz", "ba", 7)
[
-1
]
RETURN FIND_LAST("foobarbaz", "ba", 0, 4)
[
3
]
FNV64()
FNV64(text) → hash
Calculate the FNV-1A 64 bit hash for text
and return it in a hexadecimal
string representation.
- text (string): a string
- returns hash (string): FNV-1A hash as hex string
Examples
RETURN FNV64("foobar")
[
"85944171F73967E8"
]
IPV4_FROM_NUMBER()
Introduced in: v3.7.2
IPV4_FROM_NUMBER(numericAddress) → stringAddress
Converts a numeric IPv4 address value into its string representation.
- numericAddress (number): a numeric representation of an IPv4 address, for example produced by IPV4_TO_NUMBER(). The number must be an unsigned integer between 0 and 4294967295 (both inclusive).
- returns stringAddress (string): the string representation of the IPv4
address. If the input
numberAddress
is not a valid representation of an IPv4 address, the function returnsnull
and produces a warning.
Examples
RETURN IPV4_FROM_NUMBER(0)
[
"0.0.0.0"
]
RETURN IPV4_FROM_NUMBER(134744072)
[
"8.8.8.8"
]
RETURN IPV4_FROM_NUMBER(2130706433)
[
"127.0.0.1"
]
RETURN IPV4_FROM_NUMBER(3232235521)
[
"192.168.0.1"
]
RETURN IPV4_FROM_NUMBER(-23) // invalid, produces a warning
[
null
]
IPV4_TO_NUMBER()
Introduced in: v3.7.2
IPV4_TO_NUMBER(stringAddress) → numericAddress
Converts an IPv4 address string into its numeric representation.
- stringAddress (string): a string representing an IPv4 address
- returns numericAddress (number): the numeric representation of the IPv4
address, as an unsigned integer. If the input
stringAddress
is not a valid representation of an IPv4 address, the function returnsnull
and produces a warning.
Examples
RETURN IPV4_TO_NUMBER("0.0.0.0")
[
0
]
RETURN IPV4_TO_NUMBER("8.8.8.8")
[
134744072
]
RETURN IPV4_TO_NUMBER("127.0.0.1")
[
2130706433
]
RETURN IPV4_TO_NUMBER("192.168.0.1")
[
3232235521
]
RETURN IPV4_TO_NUMBER("milk") // invalid, produces a warning
[
null
]
IS_IPV4()
Introduced in: v3.7.2
IS_IPV4(value) → bool
Check if an arbitrary string is suitable for interpretation as an IPv4 address.
- value (string): an arbitrary string
- returns bool (bool):
true
ifvalue
is a string that can be interpreted as an IPv4 address. To be considered valid, the string must contain of 4 octets of decimal numbers with 1 to 3 digits length each, allowing the values 0 to 255. The octets must be separated by periods and must not have padding zeroes.
Examples
RETURN IS_IPV4("127.0.0.1")
[
true
]
RETURN IS_IPV4("8.8.8.8")
[
true
]
RETURN IS_IPV4("008.008.008.008")
[
false
]
RETURN IS_IPV4("12345.2.3.4")
[
false
]
RETURN IS_IPV4("12.34")
[
false
]
RETURN IS_IPV4(8888)
[
false
]
JSON_PARSE()
JSON_PARSE(text) → value
Return an AQL value described by the JSON-encoded input string.
- text (string): the string to parse as JSON
- returns value (any): the value corresponding to the given JSON text.
For input values that are no valid JSON strings, the function will return
null
.
Examples
RETURN JSON_PARSE("123")
[
123
]
RETURN JSON_PARSE('{"a": 1}')
[
{
"a": 1
}
]
RETURN JSON_PARSE('"abc"')
[
"abc"
]
RETURN JSON_PARSE("abc") // invalid JSON
[
null
]
JSON_STRINGIFY()
JSON_STRINGIFY(value) → text
Return a JSON string representation of the input value.
- value (any): the value to convert to a JSON string
- returns text (string): the JSON string representing
value
. For input values that cannot be converted to JSON, the function will returnnull
.
Examples
RETURN JSON_STRINGIFY(true)
[
"true"
]
RETURN JSON_STRINGIFY("abc")
[
"\"abc\""
]
RETURN JSON_STRINGIFY( [1, {'2': .5}] )
[
"[1,{\"2\":0.5}]"
]
LEFT()
LEFT(value, n) → substring
Return the n
leftmost characters of the string value
.
To return the rightmost characters, see RIGHT().
To take a part from an arbitrary position off the string,
see SUBSTRING().
- value (string): a string
- n (number): how many characters to return
- returns substring (string): at most
n
characters ofvalue
, starting on the left-hand side of the string
Examples
RETURN LEFT("foobar", 3)
[
"foo"
]
RETURN LEFT("foobar", 10)
[
"foobar"
]
LENGTH()
LENGTH(str) → length
Determine the character length of a string.
- str (string): a string. If a number is passed, it will be casted to string first.
- returns length (number): the character length of
str
(not byte length)
LENGTH()
can also determine the number of elements in an array,
the number of attribute keys of an object / document and
the amount of documents in a collection.
Examples
RETURN LENGTH("foobar")
[
6
]
RETURN LENGTH("电脑坏了")
[
4
]
LEVENSHTEIN_DISTANCE()
LEVENSHTEIN_DISTANCE(value1, value2) → distance
Calculate the Damerau-Levenshtein distance between two strings.
- value1 (string): a string
- value2 (string): a string
- returns distance (number): calculated Damerau-Levenshtein distance
between the input strings
value1
andvalue2
Examples
RETURN LEVENSHTEIN_DISTANCE("foobar", "bar")
[
3
]
RETURN LEVENSHTEIN_DISTANCE(" ", "")
[
1
]
RETURN LEVENSHTEIN_DISTANCE("The quick brown fox jumps over the lazy dog", "The quick black dog jumps over the brown fox")
[
13
]
RETURN LEVENSHTEIN_DISTANCE("der mötör trötet", "der trötet")
[
6
]
LIKE()
LIKE(text, search, caseInsensitive) → bool
Check whether the pattern search
is contained in the string text
,
using wildcard matching.
_
: A single arbitrary character%
: Zero, one or many arbitrary characters\\_
: A literal underscore\\%
: A literal percent sign
Literal backlashes require different amounts of escaping depending on the context:
\
in bind variables (Table view mode) in the Web UI (automatically escaped to\\
unless the value is wrapped in double quotes and already escaped properly)\\
in bind variables (JSON view mode) and queries in the Web UI\\
in bind variables in arangosh\\\\
in queries in arangosh- Double the amount compared to arangosh in shells that use backslashes for
escaping (
\\\\
in bind variables and\\\\\\\\
in queries)
The LIKE()
function cannot be accelerated by any sort of index. However,
the ArangoSearch LIKE()
function that
is used in the context of a SEARCH
operation is backed by View indexes.
- text (string): the string to search in
- search (string): a search pattern that can contain the wildcard characters
%
(meaning any sequence of characters, including none) and_
(any single character). Literal%
and_
must be escaped with backslashes. search cannot be a variable or a document attribute. The actual value must be present at query parse time already. - caseInsensitive (bool, optional): if set to
true
, the matching will be case-insensitive. The default isfalse
. - returns bool (bool):
true
if the pattern is contained intext
, andfalse
otherwise
Examples
LOWER()
LOWER(value) → lowerCaseString
Convert upper-case letters in value
to their lower-case counterparts.
All other characters are returned unchanged.
- value (string): a string
- returns lowerCaseString (string):
value
with upper-case characters converted to lower-case characters
Examples
RETURN LOWER("AVOcado")
[
"avocado"
]
LTRIM()
LTRIM(value, chars) → strippedString
Return the string value
with whitespace stripped from the start only.
To strip from the end only, see RTRIM().
To strip both sides, see TRIM().
- value (string): a string
- chars (string, optional): override the characters that should
be removed from the string. It defaults to
\r\n \t
(i.e.0x0d
,0x0a
,0x20
and0x09
). - returns strippedString (string):
value
withoutchars
at the left-hand side
RETURN LTRIM("foo bar")
[
"foo bar"
]
RETURN LTRIM(" foo bar ")
[
"foo bar "
]
RETURN LTRIM("--==[foo-bar]==--", "-=[]")
[
"foo-bar]==--"
]
MD5()
MD5(text) → hash
Calculate the MD5 checksum for text
and return it in a hexadecimal
string representation.
- text (string): a string
- returns hash (string): MD5 checksum as hex string
Examples
RETURN MD5("foobar")
[
"3858f62230ac3c915f300c664312c63f"
]
NGRAM_POSITIONAL_SIMILARITY()
Introduced in: v3.7.0
NGRAM_POSITIONAL_SIMILARITY(input, target, ngramSize) → similarity
Calculates the n-gram similarity
between input
and target
using n-grams with minimum and maximum length of
ngramSize
.
The similarity is calculated by counting how long the longest sequence of matching n-grams is, divided by the longer argument’s total n-gram count. Partially matching n-grams are counted, whereas NGRAM_SIMILARITY() counts only fully matching n-grams.
The n-grams for both input and target are calculated on the fly, not involving Analyzers.
- input (string): source text to be tokenized into n-grams
- target (string): target text to be tokenized into n-grams
- ngramSize (number): minimum as well as maximum n-gram length
- returns similarity (number): value between
0.0
and1.0
Examples
NGRAM_SIMILARITY()
Introduced in: v3.7.0
NGRAM_SIMILARITY(input, target, ngramSize) → similarity
Calculates n-gram similarity
between input
and target
using n-grams with minimum and maximum length of
ngramSize
.
The similarity is calculated by counting how long the longest sequence of matching n-grams is, divided by target’s total n-gram count. Only fully matching n-grams are counted, whereas NGRAM_POSITIONAL_SIMILARITY() counts partially matching n-grams too. This behavior matches the similarity measure used in NGRAM_MATCH().
The n-grams for both input and target are calculated on the fly, not involving Analyzers.
- input (string): source text to be tokenized into n-grams
- target (string): target text to be tokenized into n-grams
- ngramSize (number): minimum as well as maximum n-gram length
- returns similarity (number): value between
0.0
and1.0
Examples
RANDOM_TOKEN()
RANDOM_TOKEN(length) → randomString
Generate a pseudo-random token string with the specified length. The algorithm for token generation should be treated as opaque.
- length (number): desired string length for the token. It must be greater
or equal to 0 and at most 65536. A
length
of 0 returns an empty string. - returns randomString (string): a generated token consisting of lowercase letters, uppercase letters and numbers
Examples
REGEX_MATCHES()
REGEX_MATCHES(text, regex, caseInsensitive) → stringArray
Return the matches in the given string text
, using the regex
.
- text (string): the string to search in
- regex (string): a regular expression
to use for matching the
text
- caseInsensitive (bool, optional): if set to
true
, the matching will be case-insensitive. The default isfalse
. - returns stringArray (array): an array of strings containing the matches,
or
null
and a warning if the expression is invalid
Examples
RETURN REGEX_MATCHES("My-us3r_n4m3", "^[a-z0-9_-]{3,16}$", true)
[
[
"My-us3r_n4m3"
]
]
RETURN REGEX_MATCHES("#4d82h4", "^#?([a-f0-9]{6}|[a-f0-9]{3})$", true)
[
null
]
REGEX_SPLIT()
REGEX_SPLIT(text, splitExpression, caseInsensitive, limit) → stringArray
Split the given string text
into a list of strings at positions where
splitExpression
matches.
- text (string): the string to split
- splitExpression (string): a regular expression
to use for splitting the
text
. You can define a capturing group to keep matches - caseInsensitive (bool, optional): if set to
true
, the matching will be case-insensitive. The default isfalse
. - limit (number, optional): limit the number of split values in the result.
If no
limit
is given, the number of splits returned is not bounded. - returns stringArray (array): an array of strings, or
null
and a warning if the expression is invalid
Examples
REGEX_TEST()
REGEX_TEST(text, search, caseInsensitive) → bool
Check whether the pattern search
is contained in the string text
,
using regular expression matching.
- text (string): the string to search in
- search (string): a regular expression search pattern
- caseInsensitive (bool, optional): if set to
true
, the matching will be case-insensitive. The default isfalse
. - returns bool (bool):
true
if the pattern is contained intext
, andfalse
otherwise, ornull
and a warning if the expression is invalid
Examples
RETURN REGEX_TEST("the quick brown fox", "the.*fox")
[
true
]
RETURN REGEX_TEST("the quick brown fox", "^(a|the)\\s+(quick|slow).*f.x$")
[
true
]
RETURN REGEX_TEST("the\nquick\nbrown\nfox", "^the(\n[a-w]+)+\nfox$")
[
true
]
REGEX_REPLACE()
REGEX_REPLACE(text, search, replacement, caseInsensitive) → string
Replace the pattern search
with the string replacement
in the string
text
, using regular expression matching.
- text (string): the string to search in
- search (string): a regular expression search pattern
- replacement (string): the string to replace the
search
pattern with - caseInsensitive (bool, optional): if set to
true
, the matching will be case-insensitive. The default isfalse
. - returns string (string): the string
text
with thesearch
regex pattern replaced with thereplacement
string wherever the pattern exists intext
, ornull
and a warning if the expression is invalid
Examples
RETURN REGEX_REPLACE("the quick brown fox", "the.*fox", "jumped over")
[
"jumped over"
]
RETURN REGEX_REPLACE("An Avocado", "a", "_")
[
"An Avoc_do"
]
RETURN REGEX_REPLACE("An Avocado", "a", "_", true)
[
"_n _voc_do"
]
REVERSE()
REVERSE(value) → reversedString
Return the reverse of the string value
.
- value (string): a string
- returns reversedString (string): a new string with the characters in reverse order
Examples
RETURN REVERSE("foobar")
[
"raboof"
]
RETURN REVERSE("电脑坏了")
[
"了坏脑电"
]
RIGHT()
RIGHT(value, length) → substring
Return the length
rightmost characters of the string value
.
To return the leftmost characters, see LEFT().
To take a part from an arbitrary position off the string,
see SUBSTRING().
- value (string): a string
- length (number): how many characters to return
- returns substring (string): at most
length
characters ofvalue
, starting on the right-hand side of the string
Examples
RETURN RIGHT("foobar", 3)
[
"bar"
]
RETURN RIGHT("foobar", 10)
[
"foobar"
]
RTRIM()
RTRIM(value, chars) → strippedString
Return the string value
with whitespace stripped from the end only.
To strip from the start only, see LTRIM().
To strip both sides, see TRIM().
- value (string): a string
- chars (string, optional): override the characters that should
be removed from the string. It defaults to
\r\n \t
(i.e.0x0d
,0x0a
,0x20
and0x09
). - returns strippedString (string):
value
withoutchars
at the right-hand side
Examples
RETURN RTRIM("foo bar")
[
"foo bar"
]
RETURN RTRIM(" foo bar ")
[
" foo bar"
]
RETURN RTRIM("--==[foo-bar]==--", "-=[]")
[
"--==[foo-bar"
]
SHA1()
SHA1(text) → hash
Calculate the SHA1 checksum for text
and returns it in a hexadecimal
string representation.
- text (string): a string
- returns hash (string): SHA1 checksum as hex string
Examples
RETURN SHA1("foobar")
[
"8843d7f92416211de9ebb963ff4ce28125932878"
]
SHA512()
SHA512(text) → hash
Calculate the SHA512 checksum for text
and returns it in a hexadecimal
string representation.
- text (string): a string
- returns hash (string): SHA512 checksum as hex string
Examples
RETURN SHA512("foobar")
[
"0a50261ebd1a390fed2bf326f2673c145582a6342d523204973d0219337f81616a8069b012587cf5635f6925f1b56c360230c19b273500ee013e030601bf2425"
]
SOUNDEX()
SOUNDEX(value) → soundexString
Return the Soundex
fingerprint of value
.
- value (string): a string
- returns soundexString (string): a Soundex fingerprint of
value
Examples
SPLIT()
SPLIT(value, separator, limit) → strArray
Split the given string value
into a list of strings, using the separator
.
To split a document identifier (_id
) into the collection name and document key
(_key
), you should use the more optimized
PARSE_IDENTIFIER()
function.
- value (string): a string
- separator (string): either a string or a list of strings. If
separator
is an empty string,value
will be split into a list of characters. If noseparator
is specified,value
will be returned as array. - limit (number, optional): limit the number of split values in the result.
If no
limit
is given, the number of splits returned is not bounded. - returns strArray (array): an array of strings
Examples
RETURN SPLIT( "foo-bar-baz", "-", 1 )
[
[
"foo"
]
]
STARTS_WITH()
STARTS_WITH(text, prefix) → startsWith
Check whether the given string starts with prefix
.
There is a corresponding STARTS_WITH()
ArangoSearch function
that can utilize View indexes.
- text (string): a string to compare against
- prefix (string): a string to test for at the start of the text
- returns startsWith (bool): whether the text starts with the given prefix
Examples
RETURN STARTS_WITH("foobar", "foo")
[
true
]
RETURN STARTS_WITH("foobar", "baz")
[
false
]
STARTS_WITH(text, prefixes, minMatchCount) → startsWith
Introduced in: v3.7.1
Check if the given string starts with one of the prefixes
.
- text (string): a string to compare against
- prefixes (array): an array of strings to test for at the start of the text
- minMatchCount (number, optional): minimum number of prefixes that
should be satisfied. The default is
1
and it is the only meaningful value unlessSTARTS_WITH()
is used in the context of aSEARCH
expression where an attribute can have multiple values at the same time - returns startsWith (bool): whether the text starts with at least minMatchCount of the given prefixes
Examples
RETURN STARTS_WITH("foobar", ["bar", "foo"])
[
true
]
RETURN STARTS_WITH("foobar", ["bar", "baz"])
[
false
]
SUBSTITUTE()
SUBSTITUTE(value, search, replace, limit) → substitutedString
Replace search values in the string value
.
- value (string): a string
- search (string|array): if
search
is a string, all occurrences ofsearch
will be replaced invalue
. Ifsearch
is an array of strings, each occurrence of a value contained insearch
will be replaced by the corresponding array element inreplace
. Ifreplace
has less list items thansearch
, occurrences of unmappedsearch
items will be replaced by an empty string. - replace (string|array, optional): a replacement string, or an array of
strings to replace the corresponding elements of
search
with. Can have less elements thansearch
or be left out to remove matches. Ifsearch
is an array butreplace
is a string, then all matches will be replaced withreplace
. - limit (number, optional): cap the number of replacements to this value
- returns substitutedString (string): a new string with matches replaced (or removed)
Examples
RETURN SUBSTITUTE( "the quick brown foxx", "quick", "lazy" )
[
"the lazy brown foxx"
]
RETURN SUBSTITUTE( "the quick brown foxx", [ "quick", "foxx" ], [ "slow", "dog" ] )
[
"the slow brown dog"
]
RETURN SUBSTITUTE( "the quick brown foxx", [ "the", "foxx" ], [ "that", "dog" ], 1 )
[
"that quick brown foxx"
]
RETURN SUBSTITUTE( "the quick brown foxx", [ "the", "quick", "foxx" ], [ "A", "VOID!" ] )
[
"A VOID! brown "
]
RETURN SUBSTITUTE( "the quick brown foxx", [ "quick", "foxx" ], "xx" )
[
"the xx brown xx"
]
SUBSTITUTE(value, mapping, limit) → substitutedString
Alternatively, search
and replace
can be specified in a combined value.
- value (string): a string
- mapping (object): a lookup map with search strings as keys and replacement
strings as values. Empty strings and
null
as values remove matches. Note that there is no defined order in which the mapping is processed. In case of overlapping searches and substitutions, one time the first entry may win, another time the second. If you need to ensure a specific order then choose the array-based variant of this function - limit (number, optional): cap the number of replacements to this value
- returns substitutedString (string): a new string with matches replaced (or removed)
Examples
RETURN SUBSTITUTE("the quick brown foxx", {
"quick": "small",
"brown": "slow",
"foxx": "ant"
})
[
"the small slow ant"
]
RETURN SUBSTITUTE("the quick brown foxx", {
"quick": "",
"brown": null,
"foxx": "ant"
})
[
"the ant"
]
RETURN SUBSTITUTE("the quick brown foxx", {
"quick": "small",
"brown": "slow",
"foxx": "ant"
}, 2)
[
"the small slow foxx"
]
SUBSTRING()
SUBSTRING(value, offset, length) → substring
Return a substring of value
.
To return the rightmost characters, see RIGHT().
To return the leftmost characters, see LEFT().
- value (string): a string
- offset (number): start at
offset
, offsets start at position 0 - length (number, optional): at most
length
characters, omit to get the substring fromoffset
to the end of the string - returns substring (string): a substring of
value
Examples
RETURN SUBSTRING("Holy Guacamole!", 5)
[
"Guacamole!"
]
RETURN SUBSTRING("Holy Guacamole!", 10, 4)
[
"mole"
]
TOKENS()
TOKENS(input, analyzer) → tokenArray
Split the input
string(s) with the help of the specified analyzer
into an
array. The resulting array can be used in FILTER
or SEARCH
statements with
the IN
operator, but also be assigned to variables and returned. This can be
used to better understand how a specific Analyzer processes an input value.
It has a regular return value unlike all other ArangoSearch AQL functions and
is thus not limited to SEARCH
operations. It is independent of Views.
A wrapping ANALYZER()
call in a search expression does not affect the
analyzer
argument nor allow you to omit it.
- input (string|array): text to tokenize. Accepts recursive arrays of strings (introduced in v3.6.0).
- analyzer (string): name of an Analyzer.
- returns tokenArray (array): array of strings with zero or more elements, each element being a token.
Examples
Example query showcasing the "text_de"
Analyzer (tokenization with stemming,
case conversion and accent removal for German text):
To search a View for documents where the text
attribute contains certain
words/tokens in any order, you can use the function like this:
FOR doc IN viewName
SEARCH ANALYZER(doc.text IN TOKENS("dolor amet lorem", "text_en"), "text_en")
RETURN doc
It will match { "text": "Lorem ipsum, dolor sit amet." }
for instance. If you
want to search for tokens in a particular order, use
PHRASE() instead.
If an array of strings is passed as first argument, then each string is tokenized individually and an array with the same nesting as the input array is returned:
In most cases you will want to flatten the resulting array for further usage,
because nested arrays are not accepted in SEARCH
statements such as
<array> ALL IN doc.<attribute>
:
LET tokens = TOKENS(["quick brown", ["fox"]], "text_en") // [ ["quick", "brown"], [["fox"]] ]
LET tokens_flat = FLATTEN(tokens, 2) // [ "quick", "brown", "fox" ]
FOR doc IN myView SEARCH ANALYZER(tokens_flat ALL IN doc.title, "text_en") RETURN doc
TO_BASE64()
TO_BASE64(value) → encodedString
Return the Base64 representation of value
.
- value (string): a string
- returns encodedString (string): a Base64 representation of
value
Examples
TO_HEX()
TO_HEX(value) → hexString
Return the hexadecimal representation of value
.
- value (string): a string
- returns hexString (string): a hexadecimal representation of
value
Examples
TRIM()
TRIM(value, type) → strippedString
Return the string value
with whitespace stripped from the start and/or end.
The optional type
parameter specifies from which parts of the string the
whitespace is stripped. LTRIM()
and RTRIM() are preferred
however.
- value (string): a string
- type (number, optional): strip whitespace from the
0
– start and end of the string (default)1
– start of the string only2
– end of the string only
TRIM(value, chars) → strippedString
Return the string value
with whitespace stripped from the start and end.
- value (string): a string
- chars (string, optional): override the characters that should
be removed from the string. It defaults to
\r\n \t
(i.e.0x0d
,0x0a
,0x20
and0x09
). - returns strippedString (string):
value
withoutchars
on both sides
Examples
RETURN TRIM("foo bar")
[
"foo bar"
]
RETURN TRIM(" foo bar ")
[
"foo bar"
]
RETURN TRIM("--==[foo-bar]==--", "-=[]")
[
"foo-bar"
]
RETURN TRIM(" foobar\t \r\n ")
[
"foobar"
]
RETURN TRIM(";foo;bar;baz, ", ",; ")
[
"foo;bar;baz"
]
UPPER()
UPPER(value) → upperCaseString
Convert lower-case letters in value
to their upper-case counterparts.
All other characters are returned unchanged.
- value (string): a string
- returns upperCaseString (string):
value
with lower-case characters converted to upper-case characters
Examples
RETURN UPPER("AVOcado")
[
"AVOCADO"
]
UUID()
UUID() → UUIDString
Return a universally unique identifier value.
- returns UUIDString (string): a universally unique identifier
Examples
FOR i IN 1..3
RETURN UUID()
[
"f544bad0-e194-41d4-aea8-72b0c10c2295",
"2a976158-5bf6-40b6-ba47-9491f4f7e32c",
"b5005a71-a504-4cf5-aeae-4606991fda62"
]
Regular Expression Syntax
A regular expression may consist of literal characters and the following characters and sequences:
.
– the dot matches any single character except line terminators. To include line terminators, use[\s\S]
instead to simulate.
with DOTALL flag.\d
– matches a single digit, equivalent to[0-9]
\s
– matches a single whitespace character\S
– matches a single non-whitespace character\b
– matches a word boundary. This match is zero-length\B
– Negation of\b
. The match is zero-length[xyz]
– set of characters. Matches any of the enclosed characters (here: x, y, or z)[^xyz]
– negated set of characters. Matches any other character than the enclosed ones (i.e. anything but x, y, or z in this case)[x-z]
– range of characters. Matches any of the characters in the specified range, e.g.[0-9A-F]
to match any character in 0123456789ABCDEF[^x-z]
– negated range of characters. Matches any other character than the ones specified in the range(xyz)
– defines and matches a pattern group. Also defines a capturing group.(?:xyz)
– defines and matches a pattern group without capturing the match(xy|z)
– matches either xy or z^
– matches the beginning of the string (e.g.^xyz
)$
– matches the end of the string (e.g.xyz$
)
To literally match one of the characters that have a special meaning in regular
expressions (.
, *
, ?
, [
, ]
, (
, )
, {
, }
, ^
, $
, and \
)
you may need to escape the character with a backslash, which typically requires
escaping itself. The backslash of shorthand character classes like \d
, \s
,
and \b
counts as literal backslash. The backslash of JSON escape sequences
like \t
(tabulation), \r
(carriage return), and \n
(line feed) does not,
however.
Literal backlashes require different amounts of escaping depending on the context:
\
in bind variables (Table view mode) in the Web UI (automatically escaped to\\
unless the value is wrapped in double quotes and already escaped properly)\\
in bind variables (JSON view mode) and queries in the Web UI\\
in bind variables in arangosh\\\\
in queries in arangosh- Double the amount compared to arangosh in shells that use backslashes for
escaping (
\\\\
in bind variables and\\\\\\\\
in queries)
Characters and sequences may optionally be repeated using the following quantifiers:
x?
– matches one or zero occurrences of xx*
– matches zero or more occurrences of x (greedy)x+
– matches one or more occurrences of x (greedy)x*?
– matches zero or more occurrences of x (non-greedy)x+?
– matches one or more occurrences of x (non-greedy)x{y}
– matches exactly y occurrences of xx{y,z}
– matches between y and z occurrences of xx{y,}
– matches at least y occurrences of x
Note that xyz+
matches xyzzz, but if you want to match xyzxyz instead,
you need to define a pattern group by wrapping the sub-expression in parentheses
and place the quantifier right behind it, like (xyz)+
.