MySQL string processing function collation

MySQL string function
ASCII value of ASCII (char) return character
Bit_length (str) returns the bit length of the string
CONCAT (S1,S2...,SN) connects S1,s2...,sn to a string
Concat_ws (SEP,S1,S2...,SN) connects the S1,S2...,SN to a string and uses the Sep character interval
INSERT (STR,X,Y,INSTR) begins string str from position x, and the substring of y characters is replaced with string InStr, which returns the result
Find_in_set (str,list) analyzes a comma-delimited list of lists and, if STR is found, returns the position of STR in the list
LCASE (str) or lower (str) Returns the result of changing all characters in the string str to lowercase
Left (str,x) returns the leftmost X character in the string str
LENGTH (s) returns the number of characters in the string str
LTRIM (str) cuts the opening space from the string str
POSITION (SUBSTR,STR) returns the substring substr the first occurrence in string str
QUOTE (str) escapes single quotes in Str with a backslash

REPEAT (STR,SRCHSTR,RPLCSTR) Returns the result of the string str repeats x times
REVERSE (str) Returns the result of the reversed string str
Right (STR,X) returns the rightmost X character in the string str
RTRIM (str) Returns the space of the string str tail
STRCMP (S1,S2) comparison string S1 and S2
TRIM (str) removes all whitespace from the header and tail of the string
UCASE (str) or upper (str) returns the result of converting all characters in the string str to uppercase