String functions

The following table describes the supported string functions.

Function	Description
ASCII	Returns the ASCII code value of the leftmost character in the string as an integer.
BIT_LENGTH	Returns the length of the string in bits.
CHAR	Returns the character corresponding to each integer passed.
CHAR_LENGTH	Returns the length of the string in characters.
CONCAT	Concatenates two or more strings into a single string.
CONCAT_WS	Concatenates two or more strings with a specified separator.
ELT	Returns the Nth element from a list.
EXPORT_SET	Returns a string representing a set of values.
FIELD	Returns the index position of the first occurrence of a value in a list.
FIND_IN_SET	Returns the position of a string within a comma-separated list.
FROM_BASE64	Decodes a base64-encoded string and returns the decoded string.
HEX	Returns the hexadecimal representation of a string or number.
INSERT	Inserts a substring into a string at a specified position.
INSTR	Returns the position of the first occurrence of a substring within a string.
LCASE	Synonym for LOWER.
LEFT	Returns the leftmost n characters from a string.
LENGTH	Returns the length of the string in bytes.
LOAD_FILE	Reads a file and returns its contents as a string.
LOCATE	Returns the position of the first occurrence of a substring.
LOWER	Converts all characters in a string to lowercase.
LPAD	Pads the left side of a string with a specified character or spaces until the string reaches a specified length.
LTRIM	Removes leading spaces (spaces at the beginning of a string).
MAKE_SET	Returns the set members for a bit value.
MID	Synonym for SUBSTRING.
OCT	Returns the octal representation of a string or number.
ORD	Returns the numeric code of the leftmost character of the string.
POSITION	Returns the position of the first occurrence of a substring in a string.
QUOTE	Quotes a string for use in SQL queries.
REGEXP_INSTR	Returns the starting index of the substring that matches a regular expression pattern.
REGEXP_REPLACE	Replaces substrings that match a regular expression pattern with a replacement string.
REGEXP_SUBSTR	Returns the substring that matches the regular expression pattern.
REPEAT	Repeats a string n times and returns the resulting string.
REPLACE	Replaces occurrences of a substring with a new substring.
REVERSE	Reverses the characters in a string.
RIGHT	Returns the rightmost n characters from a string.
RPAD	Pads the right side of a string with a specified character or spaces until the string reaches a specified length.
RTRIM	Removes trailing spaces (spaces at the end of a string).
SOUNDEX	Returns the Soundex representation of a string, which is a phonetic representation used for string comparison.
SPACE	Returns a string consisting of n spaces.
STRCMP	Compares two strings and returns a result.
SUBSTRING	Extracts a substring from a string.
SUBSTRING_INDEX	Returns a substring before or after a specified delimiter in a string.
TO_BASE64	Encodes a string into base64 format and returns the encoded string.
TRIM	Removes leading and trailing spaces (or other specified characters) from a string.
UCASE	Synonym for UPPER.
UNHEX	Converts a hexadecimal string to its binary representation.
UPPER	Converts all characters in a string to uppercase.

For more information, see the MySQL documentation: String Functions and Operators.