Why both my variables output NULL? SELECT part of the cursor is working properly.
CREATE PROCEDURE p2()
BEGIN
# Account table
DECLARE accountid INT;
DECLARE accountname VARCHAR(1000);
# 1. cursor finished/done variable comes first
DECLARE done INT DEFAULT 0;
# 2. the curser declaration and select
DECLARE c_account_id_name CURSOR FOR SELECT
accountid,
accountname
FROM temp.test;
# 3. the continue handler is defined last
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET done = TRUE;
OPEN c_account_id_name;
SET accountid = 0;
SET accountname = '';
read_loop: LOOP
FETCH c_account_id_name
INTO accountid, accountname;
IF done
THEN
LEAVE read_loop;
END IF;
SELECT accountname;
END LOOP;
END;
Variable and select attribute in cursor can't be the same...it's a MySQL bug.
This will work
DROP PROCEDURE IF EXISTS p2;
DELIMITER $$
CREATE PROCEDURE p2()
BEGIN
# Account table
DECLARE v_accountidsome INT; #pay attention
DECLARE v_accountnameelst VARCHAR(1000); #pay attention
# 1. cursor finished/done variable comes first
DECLARE v_done INT DEFAULT FALSE;
# 2. the cursor declaration and select
DECLARE c_account_id_name CURSOR FOR SELECT
accountid, #pay attention
accountname #pay attention
FROM temp.test;
# 3. the continue handler is defined last
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET v_done = TRUE;
OPEN c_account_id_name;
read_loop: LOOP
FETCH c_account_id_name
INTO v_accountidsome, v_accountnameelst;
IF v_done
THEN
LEAVE read_loop;
END IF;
SELECT v_accountidsome;
SELECT v_accountnameelst;
END LOOP;
CLOSE c_account_id_name;
END $$
DELIMITER ;
CALL p2();
Find more here
According to this answer Call a stored procedure for each row returned by a query in MySQL described as following:
CREATE PROCEDURE foo() BEGIN
DECLARE done BOOLEAN DEFAULT FALSE;
DECLARE _id BIGINT UNSIGNED;
DECLARE cur CURSOR FOR SELECT id FROM objects WHERE ...;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done := TRUE;
OPEN cur;
testLoop: LOOP
FETCH cur INTO _id;
IF done THEN
LEAVE testLoop;
END IF;
CALL testProc(_id);
END LOOP testLoop;
CLOSE cur;
END
How can i set a variable and increment it over each iteration?
The following code does't work and I don't know why.
CREATE PROCEDURE foo() BEGIN
DECLARE done BOOLEAN DEFAULT FALSE;
DECLARE _id BIGINT UNSIGNED;
DECLARE counter INT DEFAULT 0;
DECLARE cur CURSOR FOR SELECT id FROM objects WHERE ...;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done := TRUE;
OPEN cur;
testLoop: LOOP
FETCH cur INTO _id;
IF done THEN
LEAVE testLoop;
END IF;
CALL testProc(_id);
counter = counter + 1;
END LOOP testLoop;
CLOSE cur;
END
I'm unable to get the result of OUT variable in this code, am I doing wrong something? can anyone help?
BEGIN
DECLARE done INT DEFAULT FALSE;
DECLARE cid INT(10);
DECLARE cuserid VARCHAR(50);
DECLARE cur1 CURSOR FOR SELECT id,username FROM tblcustomer;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
OPEN cur1;
read_loop: LOOP
FETCH cur1 INTO cid,cuserid;
IF done THEN
LEAVE read_loop;
END IF;
SET customers_list = CONCAT(customers_list,cid,':',cuserid,',');
END LOOP;
CLOSE cur1;
END
The procedure prototype is missing from your snippet, but assuming the below:
CREATE PROCEDURE foo(OUT customers_list VARCHAR(100))
BEGIN
...
SET customers_list = 'foo-list';
END ;
This is how you would retreive your "return value":
CALL foo(#var);
SELECT #var; -- outputs "foo-list"
Strictly speaking, a procedure has no "return value". A function has:
CREATE FUNCTION bar() RETURNS VARCHAR(100)
BEGIN
...
RETURN 'bar-list';
END ;
SELECT bar(); -- outputs "bar-list";
I want to create a store procedure that has ability to do multi-tasks. Then it got error message below
Error Code: 1338 Cursor declaration after handler declaration
Please look my store procedure
CREATE PROCEDURE `spTest`(OUT v1 VARCHAR(500), OUT v2 VARCHAR(500))
BEGIN
DECLARE _cur_1 CURSOR FOR
SELECT id
FROM tbl_1;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET _cur1Done = 1;
DECLARE _cur_2 CURSOR FOR
SELECT id
FROM tbl_2;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET _cur2Done = 1;
.......
You may only have one continue handler active in a block. Multiple continue handler's get the Duplicate handler declared in same block issue, even if you get the order of declarations correct ( all cursors first, then the handlers later).
You can work around this by creating a block devoted to a cursor's access. You can place these chunks of code in the same parent block, or in nested loops, or wherever.
DELIMITER $$
CREATE PROCEDURE `spTest`(OUT v1 VARCHAR(500), OUT v2 VARCHAR(500))
BEGIN
declare tbl_1_id int;
declare tbl_2_id int;
declare _cur1Done boolean default false;
declare _cur2Done boolean default false;
DECLARE _cur_1 CURSOR FOR SELECT id FROM tbl_1;
DECLARE _cur_2 CURSOR FOR SELECT id FROM tbl_2;
begin -- dedicated block to fetch from cursor 1 and update its flag
declare continue handler for not found set _cur1Done = TRUE;
fetch _cur_1 into tbl_1_id;
end;
begin -- dedicated block to fetch from cursor 2 and update its flag
declare continue handler for not found set _cur2Done = TRUE;
fetch _cur_2 into tbl_2_id;
end;
END $$
DELIMITER ;
In the manual it says
Cursor declarations must appear before handler declarations and after variable and condition declarations.
Also you can not have multiple continue handlers (how should MySQL know which continue handler is related to which cursor? Unfortunately you can't specify that), unless you nest them, for example like this:
DELIMITER $$
CREATE PROCEDURE `spTest`(OUT v1 VARCHAR(500), OUT v2 VARCHAR(500))
BEGIN
BLOCK1:BEGIN
DECLARE variable1 INT;
DECLARE _cur_1 CURSOR FOR SELECT id FROM tbl_1;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET _cur1Done = 1;
LOOP1: LOOP
FETCH _cur_1 INTO variable1;
IF _cur1Done THEN
CLOSE _cur_1;
LEAVE LOOP1;
END IF;
BLOCK2:BEGIN
DECLARE variable2 INT;
DECLARE _cur_2 CURSOR FOR SELECT id FROM tbl_2;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET _cur2Done = 1;
OPEN _cur_2;
LOOP2: LOOP
FETCH _cur_2 INTO variable2;
IF _cur2Done THEN
CLOSE _cur_2;
LEAVE LOOP2;
END IF;
END LOOP LOOP2;
END BLOCK2;
END LOOP LOOP1;
END BLOCK1;
END $$
DELIMITER ;
I wish to do something which appear a bit complicated in MySQL.
In fact, I wish to open a cursor, do a loop, and in this loop, open a second cursor using the data from the previous fetch to be executed, and re-loop on the results.
DECLARE idind INT;
DECLARE idcrit INT;
DECLARE idindid INT;
DECLARE done INT DEFAULT 0;
DECLARE done2 INT DEFAULT 0;
DECLARE curIndicateur CURSOR FOR SELECT id_indicateur FROM indicateur;
DECLARE curCritereIndicateur CURSOR FOR SELECT C.id_critere FROM critere C where C.id_indicateur=idind;
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET done = 1;
set idindid=54;
OPEN curIndicateur;
REPEAT
FETCH curIndicateur INTO idind;
open curCritereIndicateur;
REPEAT
FETCH curIndicateur INTO idcrit;
INSERT INTO SLA_DEMANDE_STATUS (iddemande,idindicateur,indicateur_status,progression) values('0009',idcrit,'OK',10.0);
UNTIL done END REPEAT;
close curCritereIndicateur;
UNTIL done END REPEAT;
CLOSE curIndicateur;
In fact, how to do 'Until done' differently for the two cursors, because you can only declare one handler for SQLSTATE?
If the first ends, the second ends too.
You need to define a new BLOCK inside your 1st cursor loop and use different Declares in that block.
Something like:
BLOCK1: begin
declare v_col1 int;
declare no_more_rows boolean1 := FALSE;
declare cursor1 cursor for
select col1
from MyTable;
declare continue handler for not found
set no_more_rows1 := TRUE;
open cursor1;
LOOP1: loop
fetch cursor1
into v_col1;
if no_more_rows1 then
close cursor1;
leave LOOP1;
end if;
BLOCK2: begin
declare v_col2 int;
declare no_more_rows2 boolean := FALSE;
declare cursor2 cursor for
select col2
from MyOtherTable
where ref_id = v_col1;
declare continue handler for not found
set no_more_rows2 := TRUE;
open cursor2;
LOOP2: loop
fetch cursor2
into v_col2;
if no_more_rows then
close cursor2;
leave LOOP2;
end if;
end loop LOOP2;
end BLOCK2;
end loop LOOP1;
end BLOCK1;
Correct me if I'm wrong, but it looks like what you are trying to do is a bulk insert of records into your "SLA_DEMANDE_STATUS" table. Include every criteria for every indicator found and default it with the values of '0009', 'OK' and 10.0 per each indicator's Criteria ID.
This can all be done in a single SQL-Insert. INSERT INTO ... from a SQL-Select...
Now, if you want to only include a single "id_indicateur" entry, you can add that to the WHERE clause of the select statement.
Notice that my SQL-Select has forced values to correspond with the columns you want to have populated. They will all be inserted to the destination table by the same name. The nice thing about this, you can just run the SQL-SELECT portion just to see the data you would EXPECT to have inserted... if its incorrect, you can adjust it to fit whatever restrictions you want.
insert into SLA_DEMANDE_STATUS
( iddemande,
idindicateur,
indicateur_status,
progression )
SELECT
'0009' iddemande,
c.id_criterere idindicateur,
'OK' indicateur_status,
10.0 progression
FROM
indicateur i;
JOIN critere c
ON i.id_indicateur = c.id_indicateur
you could use loop,and reset the value of the handle,like this:
get_something:loop
open cur;
fetch cur into temp_key;
if no_more_record=1 then
set no_more_record=0;
close cur;
leave get_something;
else
//do your job;
end if;
end loop;
Or redefine the CONTINUE HANDLE:
//...
LOOP1: LOOP
fetch cursor1
into v_col1;
if no_more_rows1 then
close cursor1;
leave LOOP1;
end if;
//...
SET no_more_rows1=false;//That's new
END LOOP LOOP1;
It seems that all select statements inside a loop execute the CONTINUE HANDLE
DECLARE _idp INT;
DECLARE _cant INT;
DECLARE _rec INT;
DECLARE done INT DEFAULT 0;
-- Definición de la consulta
DECLARE primera CURSOR FOR SELECT dp.id_prod, SUM(dp.cantidad) AS cantidad, pp.receta FROM tm_detalle_pedido AS dp INNER JOIN tm_producto_pres AS pp
DECLARE segunda CURSOR FOR SELECT id_ins, cant FROM tm_producto_ingr WHERE id_pres = _idp;
-- Declaración de un manejador de error tipo NOT FOUND
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
-- Abrimos el primer cursor
OPEN primera;
REPEAT
FETCH primera INTO _idp, _cant, _rec;
IF NOT done THEN
OPEN segunda;
block2: BEGIN
DECLARE doneLangLat INT DEFAULT 0;
DECLARE _ii INT;
DECLARE i FLOAT;
DECLARE _canti FLOAT;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET doneLangLat = 1;
REPEAT
FETCH segunda INTO _ii,_canti;
IF NOT doneLangLat THEN
IF _rec = 1 THEN
SET i = _canti * _cant;
-- Insertamos
INSERT INTO tm_inventario (id_ins,id_tipo_ope,id_cv,cant,fecha_r)
VALUES (_ii, 2, #id, i, _fecha);
END IF;
END IF;
UNTIL doneLangLat END REPEAT;
END block2;
CLOSE segunda;
END IF;
UNTIL done END REPEAT;
CLOSE primera;