I need to update a table based on the result of a subquery that brings more than 1 value, but with the query below I get the error return "Subquery returns more than 1 row". I would like to know if it is possible to make a "loop" to update the values with each result presented in my subquery below.
Complete Query
UPDATE estoque_tamanhos tam
SET tam.qtde = tam.qtde - IF(NEW.tipo = 'K', NEW.qtde_prod * NEW.qtde_lote, NEW.qtde_prod)
WHERE tam.estoques_id = (SELECT estoques_id
FROM combo_estoque
WHERE produtos_id = NEW.produtos_id)
AND UPPER(tam.tamanho) = UPPER(NEW.tamanho_prod);
Subquery that returns 2 or more values.
SELECT estoques_id FROM combo_estoque WHERE produtos_id = NEW.produtos_id
Result
produtos_id
estoques_id
246
54
246
207
In the ideal scenario, my query would execute the first value, after the second ... third ... without repeating the previous ones.
You should create a stored procedure using Cursors to iterate each result of your query.
CREATE PROCEDURE UPDATING_ROWS(PRODUTO_ID INT, qtde_prod INT, qtde_lote INT, TIPO INT)
BEGIN
DECLARE done INT DEFAULT FALSE;
DECLARE estoque_;
DECLARE cursor FOR SELECT estoques_id FROM combo_estoque WHERE produtos_id = NEW.produtos_id) AND UPPER(tam.tamanho) = UPPER(NEW.tamanho_prod)
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
OPEN cur1;
read_loop: LOOP
FETCH cur1 INTO estoque_;
IF done THEN
LEAVE read_loop;
END IF;
UPDATE estoque_tamanhos tam SET tam.qtde = tam.qtde - IF(TIPO = 'K',
qtde_prod * qtde_lote, qtde_prod)
WHERE tam.estoques_id = estoque_;
END LOOP;
END
You have to create a stored procedure like this to iterate each result of your select query. You can read more about this in this link
CREATE PROCEDURE `userCredentialsWeight`(IN data1 varchar(50), IN data2 varchar(250))
BEGIN
/* all declaration */
IF (SELECT field1 FROM user_credentials WHERE field1 = data1 LIMIT 1 )
THEN
SET DATA_WEIGHT = 75;
ELSE
SET DATA_WEIGHT = 100;
END IF;
/* More calculations here */ ---> this block contains all the calculation,
actually i am new to procedure, i have done this using
direct query from application but it requires 4 database requests
which I want to minimize here
END
Now my issue is the condition after WHERE is not getting a value of data1.
Platform - Mysql (i am using MYSQL Workbench)
Test
SELECT CASE WHEN COUNT(*) = 0
THEN 100
ELSE 75
END
INTO data_weight
FROM user_credentials
WHERE field1 = data1;
When i run this code, it gives me error. From this code, there's several task to do:
(1) update tble customer by setting the address to '90 TYT' if c_id= 1
(2) view order_no,status,c_id,item_total remarks.
(3) if item_total 0, then update table order_status by setting remarks = 'UNAVAILABLE', else select order_no,status,item_total,remarks where status = 'waiting'.
Please help me fix the error. I'm new to SQL.
#drop procedure if exists usp_GetAnything;
delimiter //
create procedure usp_GetAnything()
begin
select c_id,lname,address,city
from customer;
update customer
set address = '90 TYT'
where c_id = 1;
select o.order_no,o.o_status,c.c_id,o.item_total,o.remarks
from customer c, order_status o
where c.c_id=o.c_id;
if (o.item_total > 0) then
update order_status o
set remarks = 'UNAVAILABLE'
where order_no > '123';
else
select order_no,o_status,item_total,remarks
from order_status
where o_status = 'waiting';
end if;
end
It's failing on the line:
if (o.item_total > 0)
o is unidentified outside of the previous select clause including all the selected variables.
In order to use the results that returned from the previous select you should select ... INTO...
(select the result arguments into declared local variables).
You can find here the following example:
DELIMITER //
CREATE PROCEDURE `proc_WHILE` (IN param1 INT)
BEGIN
DECLARE variable1, variable2 INT;
SET variable1 = 0;
WHILE variable1 < param1 DO
INSERT INTO table1 VALUES (param1);
SELECT COUNT(*) INTO variable2 FROM table1;
SET variable1 = variable1 + 1;
END WHILE;
END //
You can see that variable1 and variable2 are declared in the beginning of the procedure and later on used with select ... INTO ....
I am new to writing stored Procedures and I can't seem to find the error in this procedure.
The error is marked near the where part.
I tried looking for an example where the set is done based on a if condition but I can't seem to find such an example. Can anyone point me to my error?
DELIMITER $$
CREATE PROCEDURE `incubation`.`bt_voice_modification`
(in input_slot varchar(45),in input_port varchar(45))
BEGIN
SET #SVLAN_STH:=1000;
SET #SVLAN_DTH:=999;
SET #CVLAN_DTH:=1000;
SET #FLOW_INSTANCE:=1;
UPDATE one_2_one_table
SET L2S_USER_FLOW_INSTANCE = #FLOW_INSTANCE := #FLOW_INSTANCE+1;
SET L2S_NW_SLOT = input_slot;
SET L2S_NW_PORT = input_port;
IF STH_DTH = 'STH' then
set L2S_NW_SVLAN = #SVLAN_STH :=#SVLAN_STH + 1;
ELSE
set L2S_NW_SVLAN = #SVLAN_DTH ;
set L2S_NW_CVLAN = #CVLAN_DTH :=#CVLAN_DTH + 1;
END if;
WHERE IPDSLAM_USER_SLOT = 2 AND L2S_USER_TYPE like "%gplt%";
END
Your code suggest you don't have a very clear picture of how UPDATE statement works or the exact syntax. When you put a ;, it marks the end of the (UPDATE) statement. The syntax is - for one table:
UPDATE tableX
SET columnA = what_value_should_columnA-get ,
columnB = what_value_should_columnB_get ,
...
columnX = what_value_should_columnX_get
WHERE (conditions that restrict the rows that will be affected)
ORDER BY SomeColumn ; --- this can be used in MySQL only. Standard SQL
--- (and most DBMS) do not allow ORDER BY clause in
--- UPDATE statements. Since you are using variables
--- and the order of updating affects the updated values,
--- it's essential that you include an ordering.
So, your UPDATE would be something like:
UPDATE one_2_one_table
SET L2S_USER_FLOW_INSTANCE = #FLOW_INSTANCE := #FLOW_INSTANCE+1 ,
L2S_NW_SLOT = input_slot,
L2S_NW_PORT = input_port,
L2S_NW_SVLAN = CASE WHEN STH_DTH = 'STH'
THEN #SVLAN_STH := #SVLAN_STH + 1
ELSE #SVLAN_DTH
END ,
L2S_NW_CVLAN = CASE WHEN STH_DTH = 'STH'
THEN L2S_NW_CVLAN
ELSE #CVLAN_DTH := #CVLAN_DTH + 1
END
WHERE IPDSLAM_USER_SLOT = 2
AND L2S_USER_TYPE like '%gplt%'
ORDER BY SomeColumn ;
I want to be able to pass an "array" of values to my stored procedure, instead of calling "Add value" procedure serially.
Can anyone suggest a way to do it? am I missing something here?
Edit: I will be using PostgreSQL / MySQL, I haven't decided yet.
As Chris pointed, in PostgreSQL it's no problem - any base type (like int, text) has it's own array subtype, and you can also create custom types including composite ones. For example:
CREATE TYPE test as (
n int4,
m int4
);
Now you can easily create array of test:
select ARRAY[
row(1,2)::test,
row(3,4)::test,
row(5,6)::test
];
You can write a function that will multiply n*m for each item in array, and return sum of products:
CREATE OR REPLACE FUNCTION test_test(IN work_array test[]) RETURNS INT4 as $$
DECLARE
i INT4;
result INT4 := 0;
BEGIN
FOR i IN SELECT generate_subscripts( work_array, 1 ) LOOP
result := result + work_array[i].n * work_array[i].m;
END LOOP;
RETURN result;
END;
$$ language plpgsql;
and run it:
# SELECT test_test(
ARRAY[
row(1, 2)::test,
row(3,4)::test,
row(5,6)::test
]
);
test_test
-----------
44
(1 row)
If you plan to use MySQL 5.1, it is not possible to pass in an array.
See the MySQL 5.1 faq
If you plan to use PostgreSQL, it is possible look here
I don't know about passing an actual array into those engines (I work with sqlserver) but here's an idea for passing a delimited string and parsing it in your sproc with this function.
CREATE FUNCTION [dbo].[Split]
(
#ItemList NVARCHAR(4000),
#delimiter CHAR(1)
)
RETURNS #IDTable TABLE (Item VARCHAR(50))
AS
BEGIN
DECLARE #tempItemList NVARCHAR(4000)
SET #tempItemList = #ItemList
DECLARE #i INT
DECLARE #Item NVARCHAR(4000)
SET #tempItemList = REPLACE (#tempItemList, ' ', '')
SET #i = CHARINDEX(#delimiter, #tempItemList)
WHILE (LEN(#tempItemList) > 0)
BEGIN
IF #i = 0
SET #Item = #tempItemList
ELSE
SET #Item = LEFT(#tempItemList, #i - 1)
INSERT INTO #IDTable(Item) VALUES(#Item)
IF #i = 0
SET #tempItemList = ''
ELSE
SET #tempItemList = RIGHT(#tempItemList, LEN(#tempItemList) - #i)
SET #i = CHARINDEX(#delimiter, #tempItemList)
END
RETURN
END
You didn't indicate, but if you are referring to SQL server, here's one way.
And the MS support ref.
For PostgreSQL, you could do something like this:
CREATE OR REPLACE FUNCTION fnExplode(in_array anyarray) RETURNS SETOF ANYELEMENT AS
$$
SELECT ($1)[s] FROM generate_series(1,array_upper($1, 1)) AS s;
$$
LANGUAGE SQL IMMUTABLE;
Then, you could pass a delimited string to your stored procedure.
Say, param1 was an input param containing '1|2|3|4|5'
The statement:
SELECT CAST(fnExplode(string_to_array(param1, '|')) AS INTEGER);
results in a result set that can be joined or inserted.
Likewise, for MySQL, you could do something like this:
DELIMITER $$
CREATE PROCEDURE `spTest_Array`
(
v_id_arr TEXT
)
BEGIN
DECLARE v_cur_position INT;
DECLARE v_remainder TEXT;
DECLARE v_cur_string VARCHAR(255);
CREATE TEMPORARY TABLE tmp_test
(
id INT
) ENGINE=MEMORY;
SET v_remainder = v_id_arr;
SET v_cur_position = 1;
WHILE CHAR_LENGTH(v_remainder) > 0 AND v_cur_position > 0 DO
SET v_cur_position = INSTR(v_remainder, '|');
IF v_cur_position = 0 THEN
SET v_cur_string = v_remainder;
ELSE
SET v_cur_string = LEFT(v_remainder, v_cur_position - 1);
END IF;
IF TRIM(v_cur_string) != '' THEN
INSERT INTO tmp_test
(id)
VALUES
(v_cur_string);
END IF;
SET v_remainder = SUBSTRING(v_remainder, v_cur_position + 1);
END WHILE;
SELECT
id
FROM
tmp_test;
DROP TEMPORARY TABLE tmp_test;
END
$$
Then simply CALL spTest_Array('1|2|3|4|5') should produce the same result set as the above PostgreSQL query.
Thanks to JSON support in MySQL you now actually have the ability to pass an array to your MySQL stored procedure. Create a JSON_ARRAY and simply pass it as a JSON argument to your stored procedure.
Then in procedure, using MySQL's WHILE loop and MySQL's JSON "pathing" , access each of the elements in the JSON_ARRAY and do as you wish.
An example here https://gist.githubusercontent.com/jonathanvx/513066eea8cb5919b648b2453db47890/raw/22f33fdf64a2f292688edbc67392ba2ccf8da47c/json.sql
Incidently, here is how you would add the array to a function (stored-proc) call:
CallableStatement proc = null;
List<Integer> faultcd_array = Arrays.asList(1003, 1234, 5678);
//conn - your connection manager
conn = DriverManager.getConnection(connection string here);
proc = conn.prepareCall("{ ? = call procedureName(?) }");
proc.registerOutParameter(1, Types.OTHER);
//This sets-up the array
Integer[] dataFaults = faultcd_array.toArray(new Integer[faultcd_array.size()]);
java.sql.Array sqlFaultsArray = conn.createArrayOf("int4", dataFaults);
proc.setArray(2, sqlFaultsArray);
//:
//add code to retrieve cursor, use the data.
//: