This is my stored procedure in MySQL and I want to pass a string of multiple insert queries
CREATE DEFINER=`root`#`localhost` PROCEDURE `test_stringQry`(IN qry varchar(500))<br>
BEGIN <br>
SET #input = qry; <br>
PREPARE stmt FROM #input; <br>
EXECUTE stmt;<br>
DEALLOCATE PREPARE stmt;<br>
END
When I pass a single query it works but when I pass two or more queries it gives an error
Example:
call test.test_stringQry("INSERT INTO `test`.`products`(`pro_name`,`pro_price`) VALUES('test',900.00);INSERT INTO `test`.`products`(`pro_name`,`pro_price`) VALUES('test',900.00)")
Related
Am I able to write a stored procedure with a parameter, which is the mysql query and the stored procedure returns the column names of the query?
For example I call the procedure:
call selector('select * from users')
And the procedure returns the column names.
It would be easy with information.schema but if I have a more complicated query and alias in it?
Found a solution
CREATE DEFINER=`admin`#`localhost` PROCEDURE `selector`(
IN `sql_query` VARCHAR(50))
LANGUAGE SQL
NOT DETERMINISTIC
CONTAINS SQL
SQL SECURITY DEFINER
COMMENT ''
BEGiN
drop table if exists tmp111;
SET #sql = concat('create table tmp111 as ', sql_query);
PREPARE stmt FROM #sql;
Execute stmt;
describe tmp111;
END
Then call it like:
call selector('select name as n, email as e from users')
Is it possible to pass a name of a procedure dynamically within another procedure?
The procedure name is stored in a table and based on criteria the name will be different.
If it is possible how would I accomplish this?
So far I have something like this:
SET $proc = CONCAT('CALL ',$queryString);
PREPARE stmt FROM CONCAT('CALL ', $queryString);
EXECUTE stmt;
Pretty close, just use correct prepared statement syntax:
create procedure sp_exec_proc(
in_proc char(64)
)
begin
set #proc = concat('CALL ',in_proc);
prepare stmt from #proc;
execute stmt;
end
You can then pass in the procedure name and optional parameters
call sp_exec_proc('sp_my_proc("ABC")')
I have a stored procedure where I want to perform a INSERT operation. My INSERT query is stored in a php variable $query and I want to pass it as a parameter to my stored procedure.
$query_procedure = "CALL AddStation('$query','#LID')"
How can I get this query when I am creating the stored procedure?
Actually I want to use the same stored procedure for different INSERT queries
so that I dont have to pass individual parameters to the stored procedure.
Although you can technically achieve this, as shown below, I strongly discourage you from doing it. This a very bad idea. It simple doesn't make any sense and adds no value to your code. It's vulnarable to sql injections. You loose ability to use prepared statements for insert statements themselves. It's fragile and prone to errors since you're passing query strings, etc...
You better off without a stored procedure like this at all. Just use prepared statements in your client code.
DELIMITER$$
CREATE PROCEDURE AddARow(IN _sql TEXT, OUT _lid INT)
BEGIN
SET #sql = _sql;
PREPARE stmt FROM #sql;
EXECUTE stmt;
SET _lid = LAST_INSERT_ID();
DEALLOCATE PREPARE stmt;
END$$
DELIMITER ;
Sample usage:
SET #lid = NULL;
SET #sql = 'INSERT INTO tablest (STATION_NAME, GEOGRAPHY) VALUES (''station1'',''India'')';
CALL AddARow(#sql, #lid);
SELECT #lid;
Here is SQLFiddle demo
I am trying to create a stored procedure in mysql which creates a new table on every request copies the content from another table and extracts the required data and finally drops the table. The stored procedure is quite large so I cant have EXECUTE after every query and thus I am trying to execute the query all together in a semicolon separated format. But on final execution I get Error Code: 1064.
Is the approach I am trying possible, or is there a better approach.
SET tableName = (SELECT CONCAT("table",(UNIX_TIMESTAMP(NOW()))));
SET #tquery =CONCAT('CREATE TABLE `',tableName,'` (select pt.* from post_table pt join on user u on pt.user_id=u.id where pt.client="client",pt.group="group");');
SET #tquery = CONCAT(#tquery,' SELECT * FROM ',tableName,';');
SET #tquery = CONCAT(#tquery,' DROP TABLE ',tableName,';');
PREPARE stmt FROM #tquery;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
No, it is not possible. PREPARE / EXECUTE stmt can execute only one query at a time, many statements cannot be combined. See documentation: http://dev.mysql.com/doc/refman/5.0/en/prepare.html
... a user variable that contains the text of the SQL statement. The text must represent a single statement, not multiple statements.
Anyway, to simplify your code I would create a simple procedure:
CREATE PROCEDURE exec_qry( p_sql varchar(100))
BEGIN
SET #tquery = p_sql;
PREPARE stmt FROM #tquery;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END
/
and I would call this procedure in the main procedure, in this way:
CALL exec_qry( 'CREATE TABLE t2 AS SELECT * FROM test');
CALL exec_qry( 'SELECT * FROM t2');
CALL exec_qry( 'SELECT count(*) FROM t2');
CALL exec_qry( 'SELECT avg(x) FROM t2');
CALL exec_qry( 'DROP TABLE t2');
Take a look at a demo: http://www.sqlfiddle.com/#!2/6649a/6
I understand it's possible to have dynamic SQL in user defined stored procedure on MySQL (>=5.0.13). So if we have something like this:
CREATE PROCEDURE test()
BEGIN
SET #query = "SELECT * FROM temp";
PREPARE stmt FROM #query;
EXECUTE stmt;
END
My question is: how can I use the result of the dynamic statement that is executed?
If the result is a single value you can load it into a variable.
If your query retrieves a result set of multiple records you can load these into a cursor and loop through them record by record for further processing. See http://dev.mysql.com/doc/refman/5.0/en/cursors.html