# String Functions

- [ASCII](/docs/server/reference/sql-functions/string-functions/ascii.md): Return the ASCII value of the first character. This function returns the numeric ASCII code for the leftmost character of the input string.
- [BIN](/docs/server/reference/sql-functions/string-functions/bin.md): Return the binary representation of a number. This function converts a number to its binary string equivalent.
- [BINARY Operator](/docs/server/reference/sql-functions/string-functions/binary-operator.md): Cast a string to a binary string. This operator converts a character string to a binary string, often used for case-sensitive comparisons.
- [BIT\_LENGTH](/docs/server/reference/sql-functions/string-functions/bit_length.md): Return the length of a string in bits. This function calculates the size of the string in bits (length in bytes multiplied by 8).
- [CAST](/docs/server/reference/sql-functions/string-functions/cast.md): Complete CAST reference for MariaDB. Complete function guide with syntax, parameters, return values, and usage examples with comprehensive examples and best.
- [CHAR Function](/docs/server/reference/sql-functions/string-functions/char-function.md): Return the character for each integer passed. This function interprets arguments as integer ASCII values and returns a string of those characters.
- [CHAR\_LENGTH](/docs/server/reference/sql-functions/string-functions/char_length.md): Return the length of a string in characters. This function counts the number of characters in the string, treating multi-byte characters as single units.
- [CHARACTER\_LENGTH](/docs/server/reference/sql-functions/string-functions/character_length.md): Synonym for CHAR\_LENGTH(). Returns the number of characters in the string.
- [CHR](/docs/server/reference/sql-functions/string-functions/chr.md): Return the character for a specific ASCII value. This function is similar to CHAR() but accepts a single integer argument.
- [CONCAT](/docs/server/reference/sql-functions/string-functions/concat.md): Complete CONCAT reference for MariaDB. Complete function guide with syntax, parameters, return values, and usage examples with comprehensive examples and.
- [CONCAT\_WS](/docs/server/reference/sql-functions/string-functions/concat_ws.md): Concatenate with separator. This function joins strings with a specified separator. It skips NULL values during concatenation.
- [CONVERT](/docs/server/reference/sql-functions/string-functions/convert.md): Complete CONVERT() reference: CONVERT(expr,type) and CONVERT(expr USING charset) syntax, SIGNED/UNSIGNED/BINARY/CHAR types, and CAST() differences.
- [ELT](/docs/server/reference/sql-functions/string-functions/elt.md): Return the string at a specific index. This function returns the N-th string from a list of arguments.
- [EXPORT\_SET](/docs/server/reference/sql-functions/string-functions/export_set.md): Return a string representation of bits. This function generates a string based on the bits set in a number, using specified 'on' and 'off' strings.
- [EXTRACTVALUE](/docs/server/reference/sql-functions/string-functions/extractvalue.md): Extract a value from XML. This function returns the text content of an XML fragment matching a given XPath expression.
- [FIELD](/docs/server/reference/sql-functions/string-functions/field.md): Return the index of a string in a list. This function returns the position of the first argument within the subsequent list of arguments.
- [FIND\_IN\_SET](/docs/server/reference/sql-functions/string-functions/find_in_set.md): Return the index of a string in a comma-separated list. This function finds the position of a string within a list of strings separated by commas.
- [FORMAT](/docs/server/reference/sql-functions/string-functions/format.md): Format a number. This function formats a number to a format like '#,###,###.##', rounded to a specified number of decimal places.
- [FROM\_BASE64](/docs/server/reference/sql-functions/string-functions/from_base64.md): Decode a base-64 encoded string. This function takes a base-64 string and returns the decoded binary result.
- [HEX](/docs/server/reference/sql-functions/string-functions/hex.md): Return the hexadecimal representation. This function converts a number or string to its hexadecimal string equivalent.
- [INSERT Function](/docs/server/reference/sql-functions/string-functions/insert-function.md): Insert a substring into a string. This function inserts a string within another string at a specified position and length, replacing existing characters.
- [INSTR](/docs/server/reference/sql-functions/string-functions/instr.md): Return the position of the first occurrence of a substring. This function locates a substring within a string and returns its index.
- [LCASE](/docs/server/reference/sql-functions/string-functions/lcase.md): Synonym for LOWER(). Converts a string to lowercase characters.
- [LEFT](/docs/server/reference/sql-functions/string-functions/left.md): Return the leftmost characters. This function returns the specified number of characters from the beginning (left) of a string.
- [LENGTH](/docs/server/reference/sql-functions/string-functions/length.md): Return the length of a string in bytes. This function counts the number of bytes in the string, which may differ from character count for multi-byte strings.
- [LENGTHB](/docs/server/reference/sql-functions/string-functions/lengthb.md): Return the length of a string in bytes. This function is a synonym for LENGTH() in default mode, returning the byte count.
- [LIKE](/docs/server/reference/sql-functions/string-functions/like.md): Complete LIKE operator reference: LIKE/NOT LIKE pattern matching syntax, % and \_ wildcards, ESCAPE clause, NULL behavior, and collation case-sensitivity.
- [LOAD\_FILE](/docs/server/reference/sql-functions/string-functions/load_file.md): Read a file from the server. This function reads the content of a file located on the server host and returns it as a string.
- [LOCATE](/docs/server/reference/sql-functions/string-functions/locate.md): Return the position of the first occurrence of a substring. This function finds the starting position of a substring within a string.
- [LOWER](/docs/server/reference/sql-functions/string-functions/lower.md): Convert a string to lowercase. This function returns the string with all characters converted to lowercase.
- [LPAD](/docs/server/reference/sql-functions/string-functions/lpad.md): Left-pad a string. This function pads a string on the left side with a specified string until it reaches a certain length.
- [LTRIM](/docs/server/reference/sql-functions/string-functions/ltrim.md): Remove leading spaces. This function returns the string with any leading whitespace characters removed.
- [MAKE\_SET](/docs/server/reference/sql-functions/string-functions/make_set.md): Return a set of comma-separated strings. This function returns a string consisting of substrings corresponding to the set bits in a given number.
- [MATCH AGAINST](/docs/server/reference/sql-functions/string-functions/match-against.md): Perform a full-text search. This construct searches for a text query against a set of columns indexed with a FULLTEXT index.
- [MID](/docs/server/reference/sql-functions/string-functions/mid.md): Synonym for SUBSTRING(). Returns a substring starting at a specified position for a given length.
- [NATURAL\_SORT\_KEY](/docs/server/reference/sql-functions/string-functions/natural_sort_key.md): Generate a sort key for natural ordering. This function produces a key that allows strings containing numbers to be sorted in a human-readable order.
- [NOT LIKE](/docs/server/reference/sql-functions/string-functions/not-like.md): Negated pattern matching. This operator tests whether a string does NOT match a specified SQL pattern.
- [NOT REGEXP](/docs/server/reference/sql-functions/string-functions/not-regexp.md): Negated regular expression matching. This operator tests whether a string does NOT match a specified regular expression pattern.
- [OCTET\_LENGTH](/docs/server/reference/sql-functions/string-functions/octet_length.md): Return the length of a string in bytes. This function is a synonym for LENGTH() and returns the number of bytes in the string.
- [ORD](/docs/server/reference/sql-functions/string-functions/ord.md): Return the numeric value of the first character. This function returns the code for the leftmost character, supporting multi-byte characters.
- [POSITION](/docs/server/reference/sql-functions/string-functions/position.md): Synonym for LOCATE(). Returns the position of the first occurrence of a substring within a string.
- [QUOTE](/docs/server/reference/sql-functions/string-functions/quote.md): Quote a string for SQL usage. This function produces a string ready for use as a data value in an SQL statement, escaping special characters.
- [REPEAT Function](/docs/server/reference/sql-functions/string-functions/repeat-function.md): Repeat a string. This function returns a string consisting of the input string repeated a specified number of times.
- [REPLACE Function](/docs/server/reference/sql-functions/string-functions/replace-function.md): Complete REPLACE Function reference for MariaDB. Complete function guide with syntax, parameters, return values, and usage examples for production use.
- [REVERSE](/docs/server/reference/sql-functions/string-functions/reverse.md): Reverse a string. This function returns the string with the order of its characters reversed.
- [RIGHT](/docs/server/reference/sql-functions/string-functions/right.md): Return the rightmost characters. This function returns the specified number of characters from the end (right) of a string.
- [RPAD](/docs/server/reference/sql-functions/string-functions/rpad.md): Right-pad a string. This function pads a string on the right side with a specified string until it reaches a certain length.
- [RTRIM](/docs/server/reference/sql-functions/string-functions/rtrim.md): Remove trailing spaces. This function returns the string with any trailing whitespace characters removed.
- [SFORMAT](/docs/server/reference/sql-functions/string-functions/sformat.md): Format strings with arbitrary patterns. This function allows complex string formatting using a pattern string and arguments.
- [SOUNDEX](/docs/server/reference/sql-functions/string-functions/soundex.md): Return the Soundex string. This function calculates the Soundex key for a string, allowing comparison of words that sound similar.
- [SOUNDS LIKE](/docs/server/reference/sql-functions/string-functions/sounds-like.md): Compare strings by sound. This operator tests if two strings have the same Soundex value, useful for fuzzy matching.
- [SPACE](/docs/server/reference/sql-functions/string-functions/space.md): Return a string of spaces. This function returns a string consisting of a specified number of space characters.
- [STRCMP](/docs/server/reference/sql-functions/string-functions/strcmp.md): Compare two strings. This function returns 0 if strings are equal, -1 if the first is smaller, and 1 if the first is larger.
- [SUBSTR](/docs/server/reference/sql-functions/string-functions/substr.md)
- [SUBSTRING](/docs/server/reference/sql-functions/string-functions/substring.md): Complete SUBSTRING() reference: syntax forms (pos,len, FROM/FOR), negative position from end, NULL handling, and Oracle sql\_mode position 0 behavior.
- [SUBSTRING\_INDEX](/docs/server/reference/sql-functions/string-functions/substring_index.md): Complete SUBSTRING\_INDEX() reference: SUBSTRING\_INDEX(str,delim,count) syntax, positive/negative count, case-sensitive delimiter, NULL rules.
- [TO\_BASE64](/docs/server/reference/sql-functions/string-functions/to_base64.md): Encode a string to base-64. This function converts a string argument to its base-64 encoded form.
- [TO\_CHAR](/docs/server/reference/sql-functions/string-functions/to_char.md): Convert to string. This function converts a value (often date/time) to a string, potentially using a format mask.
- [TRIM](/docs/server/reference/sql-functions/string-functions/trim.md): Remove spaces from both ends. This function removes leading and trailing whitespace (or other specified characters) from a string.
- [TRIM\_ORACLE](/docs/server/reference/sql-functions/string-functions/trim_oracle.md): Oracle-compatible TRIM function. This version of TRIM provides compatibility with Oracle's syntax for removing characters from a string.
- [Type Conversion](/docs/server/reference/sql-functions/string-functions/type-conversion.md): Understand Type Conversion in MariaDB. Learn the rules for implicit conversion during comparisons and arithmetic, and how to use CAST for predictable results.
- [UCASE](/docs/server/reference/sql-functions/string-functions/ucase.md): Synonym for UPPER(). Converts a string to uppercase characters.
- [UNHEX](/docs/server/reference/sql-functions/string-functions/unhex.md): Convert hexadecimal to string. This function interprets pairs of hexadecimal digits as numbers and converts them to the characters they represent.
- [UPDATEXML](/docs/server/reference/sql-functions/string-functions/updatexml.md): Replace a portion of XML. This function replaces a section of XML markup matching an XPath expression with a new XML fragment.
- [UPPER](/docs/server/reference/sql-functions/string-functions/upper.md): Convert a string to uppercase. This function returns the string with all characters converted to uppercase.
- [WEIGHT\_STRING](/docs/server/reference/sql-functions/string-functions/weight_string.md): Return the weight string. This function returns the binary string that represents the sorting and comparison value of the input string.
- [Regular Expressions Functions](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions.md): Learn about regular expression functions in MariaDB Server. This section details SQL functions for powerful pattern matching and manipulation of string data using regular expressions.
- [Regular Expressions Overview](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/regular-expressions-overview.md): Get an overview of regex usage. This page introduces the pattern matching capabilities and common metacharacters used in MariaDB regular expressions.
- [PCRE - Perl Compatible Regular Expressions](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/pcre.md): Understand MariaDB's regex support. This concept page explains the PCRE library integration, detailing supported syntax, character classes, and special characters.
- [REGEXP](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/regexp.md): Complete REGEXP operator reference: expr REGEXP/RLIKE pat syntax, 1/0/NULL return values, NOT REGEXP aliases, BINARY case-sensitivity, default\_regex\_flags.
- [REGEXP\_INSTR](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/regexp_instr.md): Return the index of a regex match. This function finds the starting position of the first substring that matches the given pattern.
- [REGEXP\_REPLACE](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/regexp_replace.md): Replace regex matches in a string. This function substitutes occurrences of a pattern with a specified replacement string.
- [REGEXP\_SUBSTR](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/regexp_substr.md): Return the substring matching a regex. This function extracts the actual part of the string that matches the given pattern.
- [RLIKE](/docs/server/reference/sql-functions/string-functions/regular-expressions-functions/rlike.md): Synonym for REGEXP. This operator performs a regular expression match against a string argument.