SQL String Functions
If you want to find a numerical value of a character which is in range of 0 to 255 you can use SQL ASCII function
To get the length of a string we can use SQL LENGTH() or LEN() function.
SQL CONCAT() function is used to concatenate two or more strings. MySQL allows you concatenate more than two strings while other force exactly two.
SQL CHAR or CHR function is the opposite of ASCII. It converts an integer in range 0-255 into a ascii character.
SQL replace function replaces every occurrence of the string specified as the searched string with the replacement string.
SQL Upper function allow you to convert all characters in a string into uppercase. Otherwise SQL lower function allow you to convert all characters in a string into lowercase.
In order to get a part of a string we can use sql substring or substr function.