Stored procedure calculating from a query

this example from a Well House Consultants training course
More on this [link]

This example is described in the following article(s):
• MySQL stored procedures / their use on the web from PHP - [link]

Source code: stp6 Module: S163

# We are defining a procedure which will include semicolons
# so change to some other delimiter for our instructions

DELIMITER !!!

# Clean up - get rid of any previous procedure of this name

DROP PROCEDURE IF EXISTS count_member !!!

# Define the procedure ...

CREATE PROCEDURE count_member() READS SQL DATA
BEGIN

# Declare the type of some regular variables
DECLARE i INT;
DECLARE itsdone INT;
DECLARE present_name TEXT;

# We're going to do some SQL, so set up a cursor -
# this is rather like a file handler; we'll use the
# cursor to know where we are in reading back the
# result if the query

DECLARE pointer CURSOR FOR select name from partner;

# We also need to tell MySQL what to do when it reaches
# the end of the result set, and to initialise the variable
# we used so it knows it's not at the end before it starts!

DECLARE CONTINUE HANDLER FOR NOT FOUND SET itsdone=1;
SET itsdone=0;

# Parse the results on the cursor called 'pointer'
SET i=0;
OPEN pointer;
thisloop:LOOP

        # Get a row, save the column(s) returned
        FETCH pointer INTO present_name;

        # If we failed to get data because fetch
        # triggered the end of cursor handler,
        # leave the loop
        IF itsdone=1 THEN LEAVE thisloop;
        END IF;

        # Do something (very little - it's a demo)
        # with what we got
        SET i=i+1;
END LOOP;

# When we are completely done, make up a result set
# to pass back as a result of calling this procedure.

SELECT CONCAT('There are now ',i,' partners') as rezult;
CLOSE pointer;

# End of Procedure
END;

# Signal end of definition to MySQL

!!!

# Switch back to normal delimiters

DELIMITER ;

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