Quick question,
using the code bellow, im able to use a sp to perform a delete from any table, but i dont know how to use concat to delete with the where statement.
CREATE DEFINER = `root`#`%` PROCEDURE `fn_del_t`(in t_name varchar(50), isrv char(50))
BEGIN
set #table_name = t_name;
set #iserver = isrv;
# not working with where.
set #sql_text = concat('delete from ',#table_name, 'where iserver =',#iserver);
# ---- not working with where
prepare stm from #sql_text;
execute stm;
DEALLOCATE prepare stm;
END;
call fn_del_t('the_table','localhost');
The error im receiving is:
[SQL] call fn_del_t('the_table','localhost');
[Err] 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'iserver =localhost' at line 1
Sorry for my english.
Able to solve with:
CREATE DEFINER = `root`#`%` PROCEDURE `fn_del_t`(in t_name varchar(50), isrv char(50))
BEGIN
set #table_name = t_name;
set #iserver = isrv;
#
set #sql_text = concat("delete from ",#table_name," where iserver ='",#iserver,"'");
prepare stm from #sql_text;
execute stm;
DEALLOCATE prepare stm;
END
Related
I have the following stored procedure. The idea is to get a list of databases and execute an sql statement.
DELIMITER $$
CREATE PROCEDURE updateMySQL (
IN theSQL varchar(4000)
)
BEGIN
DECLARE finished INTEGER DEFAULT 0;
DECLARE theDatabases varchar(100) DEFAULT "";
-- declare cursor for employee email
DEClARE curDatabase
CURSOR FOR
SELECT schema_name FROM information_schema.schemata where SCHEMA_NAME = 'mydb' order by 1;
-- declare NOT FOUND handler
DECLARE CONTINUE HANDLER
FOR NOT FOUND SET finished = 1;
OPEN curDatabase;
getDatabase: LOOP
FETCH curDatabase INTO theDatabases;
IF finished = 1 THEN
LEAVE getDatabase;
END IF;
-- build email list
-- SET emailList = CONCAT(theDatabases,";",emailList);
SET #sql:=CONCAT('USE ',#curDatabase);
PREPARE dynamic_statement FROM #SQL;
EXECUTE dynamic_statement;
PREPARE dynamic_statement FROM #theSQL;
EXECUTE dynamic_statement;
END LOOP getDatabase;
CLOSE curDatabase;
END$$
DELIMITER ;
I am attempting to execute the stored procedure like this,
SET #theSQL = 'ALTER VIEW `Reports` AS
SELECT DISTINCT
`tableA`.`Id` AS `Id`,
`tableA`.`letterId` AS `letterId`
FROM
`mytable` `tableA`
ORDER BY 1';
call updateMySQL(#theSQL);
EDIT There was an error on executing the procedure,
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'NULL' at line 1
I am using mysql 8.0.17
Investigate carefully MySQL 8.0 Reference Manual / SQL Statements / Prepared Statements, the section "SQL Syntax Allowed in Prepared Statements".
This section claims FULL list of statements which are allowed in Prepared statements. ALTER VIEW is NOT listed. So it is NOT allowed.
Use DROP VIEW and CREATE VIEW instead.
Always receive and investigate all error messages.
You should change this part
SET #sql:=CONCAT('USE ',#curDatabase);
PREPARE dynamic_statement FROM #SQL;
EXECUTE dynamic_statement;
PREPARE dynamic_statement FROM #theSQL;
EXECUTE dynamic_statement;
to this:
SET #sql:=CONCAT('USE ',#curDatabase);
PREPARE dynamic_statement FROM #SQL;
EXECUTE dynamic_statement;
DEALLOCATE PREPARE dynamic_statement; /* don't forget to deallocate */
/* there's a difference between the variables #theSQL and theSQL (your parameter) */
/* IIRC prepare statements need user defined variables or a syntax error occurs. Therefore I simply assign the parameter to a user-defined variable */
SET #theSQL = theSQL;
PREPARE dynamic_statement FROM #theSQL;
EXECUTE dynamic_statement;
DEALLOCATE PREPARE dynamic_statement;
Read more about user-defined variables here: https://dev.mysql.com/doc/refman/8.0/en/user-variables.html
Here the differences are explained: https://stackoverflow.com/a/1010042/447489
When you don't initialize them, their content is just NULL. Since there's a difference between user-defined variables and local variables (and also your parameter variable), your current solution did nothing.
I am working in a stored procedure that is fetching queries from a table and execute them.
The problem is that I have some queries with single/doubled quotes and it is throwing an error on execute them.
Procedure
delimiter $$
drop procedure if exists run_change_ids_queries$$
create procedure run_change_ids_queries()
begin
declare s_query TEXT;
declare done bool default false;
declare c_queries cursor for
select `query` from `queries` WHERE `executed` = 0 ORDER BY `qry_id` ASC;
declare continue handler for not found set done = true;
open c_queries;
read_loop: loop
fetch c_queries into s_query;
if done then
leave read_loop;
end if;
-- run the query
set #sql = s_query;
prepare stmt from #sql;
execute stmt;
deallocate prepare stmt;
-- update executed flag on query
set #update = CONCAT('UPDATE `queries` SET `executed` = 1 WHERE `query` LIKE \'',#sql,'\';');
prepare stmt from #update;
execute stmt;
deallocate prepare stmt;
end loop;
end$$
Query update urisegments as s inner join change_product_ids as p on concat('{"product_id":"', p.old_id, '"}') = s.primary_key_value set s.primary_key_value = CONCAT('{"product_id":', p.new_id, '"}') where s.app_namespace = 'Shop' and s.primary_key_value like '%product_id%'; is throwing error: [42000][1064] You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '{"product_id":"', p.old_id, '"}') = s.primary_key_value set s.primary_key_value ' at line 1
Workaround #01
I already tried to escape single/doubled quotes into \' and \" respectively, but it throws another error:
[42000][1064] You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '\'{\"product_id\":\"\', p.old_id, \'\"}\') = s.primary_key_value set s.primary_k' at line 1.
Don't try to concatenate the query into the SQL. Prepared statements can contain placeholders, which you fill in when you use the EXECUTE statement.
set #update = 'UPDATE `queries` SET `executed` = 1 WHERE `query` = ?');
prepare stmt from #update;
execute stmt USING #sql;
The statement is not escaped.
All single/doubled quotes should be escaped.
update urisegments as s
inner join change_product_ids as p on concat(\'{\"product_id\":\"\', p.old_id, \'\"}\') = s.primary_key_value
set s.primary_key_value = CONCAT(\'{\"product_id\":\', p.new_id, \'\"}\')
where s.app_namespace = \'Shop\' and s.primary_key_value like \'%product_id%\';
Instead of testing for the query, test for its id:
... WHERE qry_id = ?
(Add that column to the initial SELECT.)
I am trying to execute this proc below and I get an error. please can someone bail me out
----
DELIMITER $$
CREATE DEFINER=`root`#`localhost` PROCEDURE `insert_class_code`(p_newS varchar(45), p_designation varchar(45))
BEGIN
SET #table_name = p_designation;
SET #new_supply = p_newS;
SET #sql_text = concat('insert into simsed_',#table_name,' (class) values ',#new_supply) ;
PREPARE stmt FROM #sql_text;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END
----
This is the error i get.
call insert_class_code('supply 3', 'supplier)
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'supply 3'
Your below line have error:
SET #sql_text = concat('insert into simsed_',#table_name,' (class) values ',#new_supply) ;
Change it with the following code:
SET #sql_text = concat('insert into simsed_',#table_name,' (class) values ("',#new_supply,'")') ;
I have a stored procedure that works, but when I pass a value with a hyphen in it, it errors.
I call my procedure with a value like call create('server-v01',555); and I get the following error:
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-v01' at line 1
My procedure is as follows:
DELIMITER $$
CREATE PROCEDURE ct(tname varchar(20), sessionsnum INT(11))
BEGIN
DECLARE maxnum INT;
SET #s = CONCAT('INSERT INTO sessions_poll (server_name,sessions_num) VALUES(''',tname,''',',sessionsnum,')');
PREPARE stm FROM #s;
EXECUTE stm;
SET #s = CONCAT('DROP TABLE IF EXISTS ', tname);
PREPARE stm FROM #s;
EXECUTE stm;
SET #s = CONCAT('CREATE TABLE ', tname, ' (num INT, max INT)');
PREPARE stm FROM #s;
EXECUTE stm;
SELECT #maxnum:=max(sessions_num) INTO maxnum FROM sessions_poll WHERE server_name=tname AND DATE(ts)=CURDATE();
SET #s = CONCAT('INSERT INTO ', tname, ' (num,max) VALUES (', sessionsnum,',',maxnum,')');
PREPARE stm FROM #s;
EXECUTE stm;
END $$
DELIMITER ;
My question is, how can I handle a variable with a hyphen in it?
Your question is not how to handle variable with a dash, but how to handle a table with a dash. Your procedure tries to create a table with a name specified in tname. To create (or drop) a table like this you need to quote it with backticks.
DROP TABLE IF EXISTS `server-01`;
In particular you need to
SET #s = CONCAT('DROP TABLE IF EXISTS `', tname, '`');
and the same for other instances.
Whether this is what you really want to do is a question, though ;-)
This is the stored procedure I'm trying to use
DELIMITER ##
CREATE PROCEDURE exportFile()
BEGIN
DECLARE filename VARCHAR(255);
SET filename = CONCAT('~/Sample',NOW(),'.csv'));
SET #outfilestmt = concat('SELECT * INTO OUTFILE ',"'", filename,"'",' FROM Results') ;
PREPARE stmt FROM #outfilestmt;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END ##
DELIMITER ;
This is the error I get
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ');
SET #outfilestmt = concat('SELECT * INTO OUTFILE ',"'", filename,"'",' FROM R' at line 6
Desired Result:
call exportFile
--~/Sample2012-03-14-10:42:51.cvs
call exportFile
--~/Sample2012-03-14-10:42:52.cvs
call exportFile
--~/Sample2012-03-14-10:42:53.cvs
A semicolon is missing after
SET filename = CONCAT('~/Sample',NOW(),'.csv'))
and one brace is too much (also noted by Devart. Thanks). Change it to
SET filename = CONCAT('~/Sample',NOW(),'.csv');
Tested it to be sure. Works!