MySQL Functions and operators

Parentheses (...) Compare functions and operators

• =Equals
• <=>The null value is secure equal to
• <>Or!=
• <=And>
• expr BETWEEN min AND max
• COALESCE(value,...)Returns the first non-null value in a later argument list
• GREATEST(value,...)In the subsequent argument list, return the maximum value
• expr IN (value1,value2,...)If expr exists in a later argument list, returns 1, otherwise 0

logical operators

• NOT,!
• AND,&&
• OR,||
• XOR

Process Control Statements

• IF(expr1,expr2,expr3)Returns EXPR2 if Expr1 is true (expr1<>0&&expr1<>null), otherwise returns EXPR3
• IFNULL(expr1,expr2)Returns EXPR1 if EXPR1 is not NULL, otherwise returns EXPR2

String functions

• ASCII(str), returns the value of the leftmost character
• CHAR_LENGTH(str)Equivalent to CHARACTER_LENGTH(str) , returns the string str length (in characters). Note The LENGTH(str) difference, which returns the string str length, but the unit is in bytes
• CONCAT(str1,str2,...)Stitching function
• INSTR(str,substr)Returns the location of the first occurrence of substr in Str
• LOWER(str)

numeric operators and functions

• +/-/*//
• ABS(X)Absolute
• ACOS(X)
• FLOOR(X)Returns an integer value that is not greater than X

Date and Time functions

• ADDDATE(date,INTERVAL expr type)
• ADDTIME(expr1,expr2)
• CONVERT_TZ(dt,from_tz,to_tz)Convert time zone
• DATEDIFF(expr,expr2)Time difference Value
• DATE_ADD(date,INTERVAL expr type),DATE_SUB(date,INTERVAL expr type)

MySQL Functions and operators