All functions > STRING
All functions in the STRING category.
Case Conversion
| Function | DuckDB | Trino | Serving | Description |
|---|
LOWER() | ✓ | ✓ | ✓ | Returns the string with all characters converted to lowercase. |
UPPER() | ✓ | ✓ | ✓ | Returns the string with all characters converted to uppercase. |
TITLE() | ✓ | ✓ | ✓ | Returns the string with the first letter of each whitespace-delimited word in uppercase and the... |
Padding And Trimming
| Function | DuckDB | Trino | Serving | Description |
|---|
TRIM() | ✓ | ✓ | ✓ | Returns the string with whitespace from both ends removed. |
LTRIM() | ✓ | ✓ | ✓ | Returns the string with whitespace from the left (beginning) removed. |
RTRIM() | ✓ | ✓ | ✓ | Returns the string with whitespace from the right (end) removed. |
LPAD() | ✓ | ✓ | ✓ | Returns the string padded on the left to a specified length with a padding string. |
RPAD() | ✓ | ✓ | ✓ | Returns the string padded on the right to a specified length with a padding string. |
Search String
| Function | DuckDB | Trino | Serving | Description |
|---|
STARTS_WITH() | ✓ | ✓ | ✓ | Returns TRUE if a string starts with a specified prefix. |
ENDS_WITH() | ✓ | ✓ | ✓ | Returns TRUE if a string ends with a specified suffix. |
POSITION | ✓ | ✓ | ✓ | Returns the 1-based index of the first occurrence of a substring within a string. |
STRPOS() | ✓ | ✓ | ✓ | Returns the position of a substring within a string, optionally finding the N-th occurrence. |
Extraction String
| Function | DuckDB | Trino | Serving | Description |
|---|
LEFT() | ✓ | ✓ | ✓ | Returns the first `n` characters of the string (or the full string when `n` is greater than its... |
RIGHT() | ✓ | ✓ | ✓ | Returns the last `n` characters of the string (or the full string when `n` is greater than its... |
SUBSTR() | ✓ | ✓ | ✓ | Returns a substring from a string starting at a specified position. |
SPLIT() | ✓ | ✓ | ✓ | Returns an array of substrings from a string split by a delimiter. |
SPLIT_PART() | ✓ | ✓ | ✓ | Returns a specific part of a string after splitting by a delimiter. |
Transformation String
| Function | DuckDB | Trino | Serving | Description |
|---|
REVERSE() | ✓ | ✓ | ✓ | Returns the string with all characters in reverse order. |
REPLACE() | ✓ | ✓ | ✓ | Returns the string with all occurrences of a substring replaced with another substring. |
FORMAT(...) | ✓ | ✓ | ✗ | Builds a VARCHAR from a C-style format string and one scalar argument per placeholder. |
TRANSLATE() | ✓ | ✓ | ✗ | Returns a string with character-level replacements applied based on character-to-character mappings. |
BASE64_ENCODE() | ✓ | ✗ | ✗ | Encodes a string as standard Base64 text. |
BASE64_DECODE() | ✓ | ✗ | ✗ | Decodes a Base64 string back to plain text. |
HEX_ENCODE() | ✓ | ✗ | ✗ | Encodes a string as a contiguous hexadecimal string (two hex digits per byte). |
HEX_DECODE() | ✓ | ✗ | ✗ | Decodes a contiguous hexadecimal string back to plain text. |
URL_ENCODE() | ✓ | ✗ | ✗ | Encodes a string for safe use in URL components using percent-encoding (RFC 3986). |
URL_DECODE() | ✓ | ✗ | ✗ | Decodes a percent-encoded string (RFC 3986). |
Concatenation
| Function | DuckDB | Trino | Serving | Description |
|---|
CONCAT(...) | ✓ | ✓ | ✓ | Returns a single concatenated string from a list of strings. |
|| [concatenation] | ✓ | ✓ | ✓ | Concatenates two strings; chains associate to the left (same underlying `CONCAT_FN` bundle as... |
CONCAT_WS(...) | ✓ | ✓ | ✓ | Returns a concatenated string from a list of strings with a separator between each element. |
Character
| Function | DuckDB | Trino | Serving | Description |
|---|
LENGTH() | ✓ | ✓ | ✓ | Returns the number of characters in a string. |
CHR() | ✓ | ✓ | ✓ | Returns the character corresponding to the given Unicode code point. |
CODEPOINT() | ✓ | ✓ | ✓ | Returns the Unicode code point of the first character in a string. |
Distance
| Function | DuckDB | Trino | Serving | Description |
|---|
HAMMING_DISTANCE() | ✓ | ✓ | ✓ | Returns the Hamming distance between two strings of equal length. |
LEVENSHTEIN_DISTANCE() | ✓ | ✓ | ✓ | Returns the Levenshtein (edit) distance between two strings. |
Phonetic
| Function | DuckDB | Trino | Serving | Description |
|---|
WORD_STEM() | ✗ | ✓ | ✗ | Returns the stem (root form) of a word using language-specific stemming rules. |
SOUNDEX() | ✗ | ✓ | ✗ | Returns a four-character Soundex code representing the phonetic sound of a string. |
Validation String
| Function | DuckDB | Trino | Serving | Description |
|---|
LUHN_CHECK() | ✗ | ✓ | ✗ | Returns TRUE if a string passes the Luhn algorithm (modulus 10 checksum). |
Hash
| Function | DuckDB | Trino | Serving | Description |
|---|
MD5() | ✓ | ✓ | ✓ | Returns the MD5 hash of a string as a 32-character hexadecimal string. |
SHA1() | ✓ | ✓ | ✗ | Returns the SHA-1 hash of a string as a 40-character hexadecimal string. |
SHA256() | ✓ | ✓ | ✓ | Returns the SHA-256 hash of a string as a 64-character hexadecimal string. |
Regex
| Function | DuckDB | Trino | Serving | Description |
|---|
REGEX_CONTAINS() | ✓ | ✓ | ✓ | Returns TRUE if the haystack string contains a match for the regular expression pattern (substring... |
REGEX_MATCH() | ✓ | ✓ | ✓ | Returns TRUE if the entire string matches the regular expression pattern. Unlike REGEX_CONTAINS,... |
REGEX_EXTRACT_FIRST() | ✓ | ✓ | ✓ | Returns the first substring that matches the pattern, optionally selecting a capture group index (0... |
REGEX_EXTRACT_ALL() | ✓ | ✓ | ✗ | Returns an array of every non-overlapping substring that matches the pattern, in left-to-right... |
REGEX_SPLIT() | ✓ | ✓ | ✗ | Splits a string by a regular expression pattern and returns the parts between matches as an array. |
REGEX_REPLACE_FIRST() | ✓ | ✓ | ✓ | Returns the haystack with the first regular-expression match replaced by the replacement string. |
REGEX_REPLACE_ALL() | ✓ | ✓ | ✓ | Returns the haystack with every non-overlapping regular-expression match replaced by the... |
Summary
Functions in this category: 48