MSSQL and Mysql User-defined functions and stored procedures _ MySQL

MSSQL and Mysql User-defined functions and stored procedures mysql and mssql user-defined functions without the cut string, such as in the input
(A, B, C ),
We need to obtain a column

Data
A
B
C

This is not included in the system itself. you need to define a function. first look at the custom function of MSSQL:
CREATE function StrSplit (@ c varchar (2000), @ split varchar (2) = ',')
Returns @ t table (col varchar (100 ))
As
Begin

While (charindex (@ split, @ c) <> 0)
Begin
Insert @ t (col) values (substring (@ c, 1, charindex (@ split, @ c)-1 ))
Set @ c = stuff (@ c, 1, charindex (@ split, @ c ),'')
End
Insert @ t (col) values (@ c)
Return
End

GO

When using
Select * from dbo. StrSplit ('52, 50, 55 ',','))

You can.

In MYSQL, I also want to use user-defined functions. However, the current version does not support returning functions of the table type, so I have to consider using stored procedures.
First, understand the statement for creating a temporary table in mysql:

Set global log_bin_trust_function_creators = 1;
DELIMITER $

Drop function if exists 'myf' $

Create definer = 'root' @ '%' FUNCTION 'myf' () RETURNS varchar (50) CHARSET utf8
Begin
Return concat ('-function ');
End $

DELIMITER;

Then let's take a look at the usage:
SELECT Myf ('myf? ');

Then there is the stored procedure:

DELIMITER //

Drop procedure if exists split_string //
Create procedure split_string (
IN input VARCHAR (2000)
, IN 'delimiter' VARCHAR (10)
)
SQL SECURITY INVOKER
COMMENT
'Splits a supplied string using the given delimiter,
Placing values in a temporary table'
BEGIN
DECLARE cur_position int default 1;
DECLARE remainder VARCHAR (2000 );
DECLARE cur_string VARCHAR (1000 );
DECLARE delimiter_length tinyint unsigned;

Drop temporary table if exists SplitValues;
Create temporary table SplitValues (
Value VARCHAR (1000) NOT NULL PRIMARY KEY
) ENGINE = MyISAM;

SET remainder = input;
SET delimiter_length = CHAR_LENGTH (delimiter );

WHILE CHAR_LENGTH (remainder)> 0 AND cur_position> 0 DO
SET cur_position = INSTR (remainder, 'delimiter ');
IF cur_position = 0 THEN
SET cur_string = remainder;
ELSE
SET cur_string = LEFT (remainder, cur_position-1 );
End if;
If trim (cur_string )! = ''THEN
Insert into SplitValues VALUES (cur_string );
End if;
SET remainder = SUBSTRING (remainder, cur_position + delimiter_length );
End while;

END //

DELIMITER;

/*
Tests
*/

CALL split_string ('Steve, Jan, Bobby, Jay, Kaj, Colin ',',');

SELECT * FROM SplitValues;

Create temporary table TestJoin (join_field VARCHAR (20) primary key) ENGINE = MEMORY;

Insert into TestJoin VALUES ('kaj'), ('Colin ');

SELECT tj. * FROM TestJoin tj
Inner join SplitValues sv
ON tj. join_field = sv. value;
// This code is from the MYSQL official website and I have not verified it