How to make a while in a stored procedure with phpmyadmin, error #1064 - mysql

Question

I try to create a stored procedure in phpmyadmin, but I get a error 1064 on line 12 (where the WHILE is). This is the first time I try to create a stored procedure.
BEGIN
DECLARE product_id INT;
DECLARE product_min_age nvarchar(500);
DECLARE cur CURSOR for
SELECT product_min_age, product_id FROM _vm_product;
open cur;
fetch next from cur into product_min_age, product_id;
while FETCH_STATUS = 0 BEGIN
INSERT INTO _virtuemart_product_customfields (virtuemart_product_id, virtuemart_custom_id, customfield_value, customfield_params) VALUES
( product_id, 5, product_min_age, 'addEmpty=0|selectType=0|');
fetch next from cur into product_min_age,product_id;
END;
close cur;
END
Thank you

Answer 1

You should change that to below. See Documentation for more information.
open cur;
read_loop: LOOP
fetch cur into product_min_age, product_id;
INSERT INTO _virtuemart_product_customfields (virtuemart_product_id, virtuemart_custom_id, customfield_value, customfield_params) VALUES
( product_id, 5, product_min_age, 'addEmpty=0|selectType=0|');
END LOOP;
close cur;

Answer 2

The accepted answer is indeed correct and so is your own answer. Unfortunately the approach is completely wrong!
One does not generally perform sql queries inside a loop unless as a last resort. Select / loop / insert is in fact a frequent pattern followed by people writing their first stored procedure. but there is a better way, a much much better way. And that is INSERT .. SELECT
With INSERT ... SELECT, you can quickly insert many rows into a table
from one or many tables. For example:
Your complex stored procedure reduces to:
INSERT INTO _virtuemart_product_customfields (virtuemart_product_id, virtuemart_custom_id, customfield_value, customfield_params)
SELECT product_id, 5, product_min_age, 'addEmpty=0|selectType=0|'
FROM _vm_product
That's it, just a simple select, no stored procedures!
A second issue is that you are stored delimited text in a column.
addEmpty=0|selectType=0|
I am not quite sure why you are doing this but it's most unusual.

Answer 3

If someone want to see my final result:
BEGIN
DECLARE _product_id INT;
DECLARE _product_min_age nvarchar(500);
DECLARE done INT DEFAULT 0;
DECLARE cur CURSOR for SELECT product_min_age, product_id FROM _vm_product;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
open cur;
read_loop: LOOP
fetch cur into _product_min_age, _product_id;
IF done = 1 THEN
LEAVE read_loop;
END IF;
INSERT INTO _virtuemart_product_customfields (virtuemart_product_id, virtuemart_custom_id, customfield_value, customfield_params) VALUES
( _product_id, 5, _product_min_age, 'addEmpty=0|selectType=0|');
END LOOP;
close cur;
END