MySQL offers many built-in string functions. MySQL string function can be categorize as String Comparison Functions, Regular Expressions and Character Set and Collation of Function.
| Function | Description |
|---|---|
| ASCII() | Return numeric value of left-most character |
| BIN() | Return a string that contains binary data of a number |
| BIT_LENGTH() | Return length of argument in bits |
| CHAR_LENGTH() | Return number of characters in given string |
| CHARACTER_LENGTH() | Synonym for CHAR_LENGTH() |
| CONCAT() | Return combined string |
| CONCAT_WS() | Return combined string with separator |
| ELT() | Return string at index number |
| EXPORT_SET() | Return a string such that for every bit set in the value bits |
| FIELD() | Return the position of the first argument in the subsequent arguments |
| FIND_IN_SET() | Return the index position of the first argument within the second argument |
| FORMAT() | Formats the number like '#,###,###.##' and rounded with decimal places, and returns the result as a string. |
| FROM_BASE64() | Returns the decoded result as a binary string |
| HEX() | Return a hexadecimal representation of a string value |
| INSERT() | Insert a substring at the specified position up to the specified number of characters |
| INSTR() | Return the position of the first occurrence of substring |
| LCASE() | Synonym for LOWER() |
| LEFT() | Return the leftmost number of specified characters from string |
| LENGTH() | Return the length of a string |
| LIKE | Simple pattern matching |
| LOAD_FILE() | Reads the file and returns the file contents as a string |
| LOCATE() | Return the position of the first occurrence of substring |
| LOWER() | Return the string in lowercase |
| LPAD() | Return the string, left-padded with the specified string |
| LTRIM() | Remove left spaces from string |
| MAKE_SET() | Return a set of comma-separated strings |
| MATCH | Perform full-text search |
| MID() | Return a substring from specified position |
| NOT LIKE | Negation of simple pattern matching |
| NOT REGEXP | Negation of REGEXP |
| OCT() | Return a string containing octal representation of a number |
| OCTET_LENGTH() | Synonym for LENGTH() |
| ORD() | Return character code for leftmost character of the argument |
| POSITION() | Synonym for LOCATE() |
| QUOTE() | Escape the argument for use in an SQL statement |
| REGEXP | Synonym for REGEXP_LIKE() |
| REPEAT() | Repeat a string the specified number of times |
| REPLACE() | Replace occurrences of a specified string |
| REVERSE() | Reverse the characters in a string |
| RIGHT() | Return the specified rightmost number of characters |
| RLIKE | Synonym for REGEXP_LIKE() |
| RPAD() | Append string the specified number of times |
| RTRIM() | Remove trailing spaces |
| SOUNDEX() | Return a soundex string |
| SOUNDS LIKE | Compare sounds |
| SPACE() | Return a string of the specified number of spaces |
| STRCMP() | Compare two strings |
| SUBSTR() | Return the substring as specified |
| SUBSTRING() | Return the substring as specified |
| SUBSTRING_INDEX() | Return a substring from a string before the specified number of occurrences of the delimiter |
| TO_BASE64() | Return the string converted to a base-64 string |
| TRIM() | Remove left and right spaces |
| UCASE() | Synonym for UPPER() |
| UNHEX() | Return a string containing hex representation of a number |
| UPPER() | Convert to uppercase |
| WEIGHT_STRING() | Return the weight string for a string |