1.) alternative for stored procedure in mysql which can be altered rather than drop and create again
2.) easy ways to maintain database version i am currently creating log.sql files manually such as example log.sql file
ALTER TABLE `ship`
CHANGE COLUMN `is_deleted` `is_deleted` INT(11) NULL DEFAULT 0 ;
DROP procedure IF EXISTS `get_ship`;
DELIMITER ;;
CREATE PROCEDURE `get_ship`(
)
BEGIN
do something;
end if;
END ;;
DELIMITER ;
Is there an better and easy way to create such sql log files,
I have already tried MYSQL workbench
When you are redefining a table structure with any of the following
drop column,
change column,
modify column,
add column,
rename table
and your stored procedure has dependency on the same table and its pre-defined columns,
then you don't have a choice but redefine part of your stored procedure.
And this can only be achieved by dropping and re-creating the procedure again.
As per documentation on ALTER PROCEDURE Syntax, in MySQL,
However, you cannot change the parameters or body of a stored procedure using this statement; to make such changes, you must drop and re-create the procedure using DROP PROCEDURE and CREATE PROCEDURE.
add column may not require re-building your stored procedure unless the new column too participates in the procedure's algorithm.
Related
I have a stored procedure designed to generate a new, 'derived' table. In this procedure I then want to add a column using ALTER TABLE. However, despite an almost identical stored procedure working fine, and despite being able to add this manually as a stored procedure to the database using MySQL Workbench, when I pass the code to the server using SOURCE (i.e. SOURCE workload.sql), I get an error 1146 (42502) 'Table 'workload._convenor_workload' doesn't exist.' (I'm doing this in Emacs as part of a org-babel block, but this is essentially just passing raw SQL to the server.)
As background, I'm in the process of migrating SQL code from a setting where I was running it raw to create my final database to one where I'd like this code to be called via triggers.
Setup: mysql Ver 8.0.16 for macos10.14 on x86_64 (MySQL Community Server - GPL)
I've tried rewriting this as a prepared statement, was unsuccessful, and have been scouring Stack Overflow. This is my first MySQL project and my reading of the documentation suggests that ALTER TABLE is a perfectly legal thing to do in a stored procedure. It's likely that I'm making a schoolboy error somewhere but at the moment I'm banging my head.
Elsewhere in my SQL, this code works in a stored procedure (ALTER TABLE function does not throw an error):
CREATE TABLE _assessment_allocations AS SELECT Assessment_ID,
IFNULL(SUM(_total_first_marking_hours),0) AS _total_first_marking_hours_sum,
GROUP_CONCAT(DISTINCT _total_first_marking_hours_needed) AS _total_first_marking_hours_needed,
GROUP_CONCAT(DISTINCT Prog_ID) AS prog_id
FROM
_marking_workload
GROUP BY Prog_ID, Assessment_ID;
ALTER TABLE _assessment_allocations
ADD COLUMN _assessment_variance DECIMAL(5,2);
However, the code that throws the error is this (specifically, the ALTER TABLE function; I've added the stored procedure code in case this is helpful). Note that this code does not throw an error when ingested by MySQL outside a stored procedure:
USE `workload`;
DELIMITER $$
CREATE DEFINER=`root`#`localhost` PROCEDURE `module_administration_convenor`()
-- Begin by selecting elements of the ~modules~ table
CREATE TABLE `_convenor_workload` AS
SELECT Modules.Module_Code,
Modules.Module_Name,
Modules.Module_Convenor_ID,
Modules.Module_Convenor_Share,
Modules.Student_Tally,
Modules.Additional_Hours,
Modules.Convening_Notes,
Modules.Active_Status
FROM modules;
-- Add a 'Convenor' column
ALTER TABLE `_convenor_workload` ADD COLUMN `Name` VARCHAR(255) DEFAULT 'Convenor';
\* Other stuff *\
END$$
DELIMITER ;
My aim is to avoid throwing this error. I'd like to get this stored procedure actually stored! (Just like the previous stored procedure that does much the same and does not throw an error.) I'm aware that there are some back-tick and style differences between the working and non-working code, but I'm guessing these aren't super important.
As I said, I have a strong suspicion that I'm overlooking something obvious here...
As mentioned by Solarflare in the comments, you are missing a begin so the alter table is executing as a separate action. If you wrap it with begin and end then it treats all the code as the stored procedure.
USE `workload`;
DELIMITER $$
CREATE DEFINER=`root`#`localhost` PROCEDURE `module_administration_convenor`()
Begin
-- Begin by selecting elements of the ~modules~ table
CREATE TABLE `_convenor_workload` AS
SELECT Modules.Module_Code,
Modules.Module_Name,
Modules.Module_Convenor_ID,
Modules.Module_Convenor_Share,
Modules.Student_Tally,
Modules.Additional_Hours,
Modules.Convening_Notes,
Modules.Active_Status
FROM modules;
-- Add a 'Convenor' column
ALTER TABLE `_convenor_workload` ADD COLUMN `Name` VARCHAR(255) DEFAULT 'Convenor';
END
$$
DELIMITER ;
i'm new to MySQL.
I need to call stored procedure from a stored procedure and use the first stored procedure as a table.
How to do this without use temporary table?
How to do this without use temporary table?
create a fact table then
Not sure why there is a requirement saying: can't use temporary table as you are using store procedure. but that must be unreasonable.
if the RDBS takes care of that for you , the underlying mechanism is still store the 1st result set somewhere in the memory as middle step result. temporary table for you.
so just: create a temporary table, call the store procedure, insert data into that . why not
1.) alternative for stored procedure in mysql which can be altered rather than drop and create again
2.) easy ways to maintain database version
i am currently creating log.sql files manually such as
example log.sql file
ALTER TABLE `ship`
CHANGE COLUMN `is_deleted` `is_deleted` INT(11) NULL DEFAULT 0 ;
DROP procedure IF EXISTS `get_ship`;
DELIMITER ;;
CREATE PROCEDURE `get_ship`(
)
BEGIN
do something;
end if;
END ;;
DELIMITER ;
Is there an better and easy way to create such sql log files,
I have already tried MYSQL workbench
Just as you create stored procedures using the CREATE PROCEDURE command, you alter them with ALTER PROCEDURE. The advantage of using ALTER PROCEDURE to change a stored procedure is that it preserves access permissions, whereas CREATE PROCEDURE doesn't. A key difference between them is that ALTER PROCEDURE requires the use of the same encryption and recompile options as the original CREATE PROCEDURE statement. If you omit or change them when you execute ALTER PROCEDURE, they'll be omitted or changed permanently in the actual procedure definition.
A procedure can contain any valid Transact-SQL command except these: CREATE DEFAULT, CREATE FUNCTION, CREATE PROC, CREATE RULE, CREATE SCHEMA, CREATE TRIGGER, CREATE VIEW, SET SHOWPLAN_TEXT, and SET SHOWPLAN_ALL. These commands must reside in their own command batches, and, therefore, can't be part of a stored procedure. Procedures can create databases, tables, and indexes, but not other procedures, defaults, functions, rules, schemas, triggers, or views
but u could try out views in mysql for u case
using MySQL 5.1.36, I am trying to write trigger which drops scratch tables form "scratch" database.
CREATE DEFINER=`root`#`localhost` TRIGGER
`jobq`.`DropScratch`
BEFORE DELETE ON jobq.jobq FOR EACH ROW
BEGIN
DECLARE tblname VARCHAR(128);
set tblname=concat('scratch.',OLD.jobname);
DROP TABLE IF EXISTS tblname;
END;
I am always getting an error:
Explicit or implicit commit is not allowed in stored function or trigger.
Can I somehow overcome this restriction?
Thank you beforehand
Arman
The primary problem here is that you are not allowed to drop a table within a trigger. That's what the error message is getting at when it says "implicit commit" is not allowed. The drop table does an implicit commit.
So you will need to figure out a different way to do this other than a trigger. One way would be to set up a cron job which compares the data in information_schema.tables to the jobq table to look for tables in the scratch DB that can be dropped, and then drop them.
I should also point out that the way you are trying to dynamically create a drop table statement will not work. That is going to drop a table named literally "tblname", not "scratch.jobname". If you want to drop a table dynamically you will need to build the drop table statement in a separate scripting language, such as python, perl, shell, etc.
Good luck!
We have set up a replication scheme master/slave and we've had problems lately because some users wrote directly on the slave instead of the master, making the whole setup inconsistent.
To prevent these problems from happening again, we've decided to remove the insert, delete, update, etc... rights from the users accessing the slave. Problems is that some stored procedure (for reading) require temporary tables.
I read that changing the global variable read_only to true would do what I want and allow the stored procedures to work correctly ( http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html#sysvar_read_only ) but I keep getting the error :
The MySQL server is running with the --read-only option so it cannot
execute this statement (1290)
The stored procedure that I used (for testing purpose) is this one :
DELIMITER $$
DROP PROCEDURE IF EXISTS `test_readonly` $$
CREATE DEFINER=`dbuser`#`%` PROCEDURE `test_readonly`()
BEGIN
CREATE TEMPORARY TABLE IF NOT EXISTS temp
(
`BT_INDEX` int(11),
`BT_DESC` VARCHAR(10)
);
INSERT INTO temp (BT_INDEX, BT_DESC) VALUES (222,'walou'), (111,'bidouille');
DROP TABLE temp;
END $$
DELIMITER ;
The create temporary table and the drop table work fine with the readonly flag - if I comment the INSERT line, it runs fine- but whenever I want to insert or delete from that temporary table, I get the error message.
I use Mysql 5.1.29-rc. My default storage engine is InnoDB.
Thanks in advance, this problem is really driving me crazy.
There seems to be a bug opened about this for the 6.0 beta:
http://bugs.mysql.com/bug.php?id=33669
[3 Jan 2008 19:26] Philip Stoev
Description: When the server is
started with --read-only, updates to
Falcon temporary tables are not
allowed.
You might want to add your findings there.