replace does only trigger one trigger in mariadb - mysql

I have the following tables
CREATE TABLE `trigger_root` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`p` int(11) DEFAULT NULL,
PRIMARY KEY (`id`)
);
CREATE TABLE `trigger_test` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`p` int(11) DEFAULT NULL,
PRIMARY KEY (`id`)
);
and the following triggers
DELIMITER ||
CREATE TRIGGER tit
BEFORE INSERT ON trigger_root
FOR EACH ROW
BEGIN
INSERT INTO trigger_test (p) values (NEW.p);
END ||
CREATE TRIGGER tdt
BEFORE delete ON trigger_root
FOR EACH ROW
BEGIN
delete from trigger_test where p=OLD.p;
END ||
DELIMITER ;
However if I use the following statement
replace into trigger_root(id,p) select id,p from trigger_root;
only the delete trigger is called. if i remove the delete trigger the insert trigger is called.
so it seems replace only triggers one but not both triggers
is that a general restriction or do I do something wrong?

I found the error. the insert nedds to be after rahter than before.

Related

Error importing a previously exported mysql trigger

I had a mysql trigger that has been working, I exported it and removed it and am trying to put it back, but I keep running into the following error:
#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 '' at line 12
My trigger is:
CREATE TRIGGER `accounts_tracking` AFTER UPDATE ON `accounts`
FOR EACH ROW BEGIN
IF( NEW.`check_level` != OLD.`check_level` ) THEN
INSERT INTO `accounts_tracking` ( `change_type`, `account_id`, `field`, `old_int`, `new_int`, `old_time`, `new_time` )
VALUES
( "1",
OLD.id,
"check_level",
OLD.`check_level`,
NEW.`check_level`,
UNIX_TIMESTAMP(),
UNIX_TIMESTAMP());
END IF;
END
Line #12 is the 2nd UNIX_TIMESTAMP()
My table structure is as follows:
CREATE TABLE `accounts_tracking` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`change_type` smallint(5) unsigned NOT NULL,
`account_id` int(10) unsigned NOT NULL,
`field` varchar(255) NOT NULL,
`old_int` int(11) NOT NULL,
`new_int` int(11) NOT NULL,
`new_time` int(10) unsigned NOT NULL,
`old_time` int(10) unsigned NOT NULL,
PRIMARY KEY (`id`),
KEY `account_id` (`account_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
Server type: MySQL
Server version: 5.1.73-log
Thanks.
As barranka suggested in comments section, you need to enclose this trigger in a delimiter, like so:
DELIMITER $$
CREATE TRIGGER `accounts_tracking` AFTER UPDATE ON `accounts`
FOR EACH ROW BEGIN
IF( NEW.`check_level` != OLD.`check_level`) THEN
INSERT INTO `accounts_tracking` ( `change_type`, `account_id`, `field`, `old_int`, `new_int`, `old_time`, `new_time` )
VALUES
( "1",
OLD.id,
"check_level",
OLD.`check_level`,
NEW.`check_level`,
UNIX_TIMESTAMP(),
UNIX_TIMESTAMP());
END IF;
END$$
DELIMITER ;
The reason is that by adding a Begin and End to the statement you are essentially creating a stored routine/procedure with the trigger itself. In order to run multiple statements, like in stored routine/procedure, you need to add delimiters.
In other cases where you do not have the Begin and End within the trigger, you do not need the delimiters. For Example:
CREATE TABLE account (acct_num INT, amount DECIMAL(10,2));
CREATE TRIGGER ins_sum BEFORE INSERT ON account FOR EACH ROW SET #sum = #sum + NEW.amount;

delete trigger when condition is met

I know it is a simple question but i am not finding the answer anywhere.
That's my table:
city | CREATE TABLE `city` (
`ID` int(11) NOT NULL,
`Name` char(35) NOT NULL DEFAULT '',
`CountryCode` char(3) NOT NULL DEFAULT '',
`District` char(20) NOT NULL DEFAULT '',
`Population` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`ID`),
KEY `FKcode99` (`CountryCode`),
CONSTRAINT `FKcode99` FOREIGN KEY (`CountryCode`) REFERENCES `country` (`code`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
The question is: If you want to delete a city, the population must be 275,000 or less.
I tried
ALTER TABLE `world`.`city`
RENAME TO `world`.`DeleteCity` ;
USE `world`;
DELIMITER $$
DROP TRIGGER IF EXISTS world.DeleteCity_ADEL$$
USE `world`$$
CREATE TRIGGER `DeleteCity_ADEL` AFTER DELETE ON `DeleteCity` FOR EACH ROW
IF (OLD.population <= 275000) THEN
DELETE FROM city WHERE NEW.name=OLD.name;
END IF;
$$
DELIMITER ;
but it doesn't work. Can anybody help me?
I would do it in this way:
CREATE TRIGGER `DeleteCity_ADEL` BEFORE DELETE ON `DeleteCity` FOR EACH ROW
IF (OLD.population > 275000) THEN
SIGNAL SQLSTATE '45123'
SET MESSAGE_TEXT = 'If you want to delete a city, the population must be 275,000 or less.';
END IF;
/
This trigger raises an error when somone is trying to delete a record with population > 275,000 and returns a clear explanation (error message) to him.
If population is less or equal than 275,000, the record is silently deleted.

Reserve/Assign a new row in another table with each row added in one

I'll like to find out if it's possible to do the following:
after insertion of data into table a, a row will be created automatically in table b and the Note_Id (its primary key) will be stored in one of the attributes (which is a foreign key that references to the primary key in table b) in table a.
CREATE TABLE table_a ( D_Id int(5) NOT NULL AUTO_INCREMENT,
User_Id int(8) not null,
Note_Id int(5) not null, -- this is the foreign key that points to table b
PRIMARY KEY (D_Id) ) ENGINE=InnoDB DEFAULT CHARSET=latin1;
CREATE TABLE table_b ( Note_Id int(5) NOT NULL AUTO_INCREMENT,
Note_Description varchar(50) null,
PRIMARY KEY (Note_Id) ) ENGINE=InnoDB DEFAULT CHARSET=latin1;
Thanks!
delimiter $$
CREATE TRIGGER ins_Document
AFTER INSERT ON TABLE_A FOR EACH ROW
BEGIN
set #notenum=(Select max(Note_Id) from TABLE_B);
if(#notenum=0) then begin new.Note_Id=1;
end;
else
new.Note_Id=#notenum+1;
end if;
INSERT INTO TABLE_B (Note_Id) VALUES (NEW.Note_Id);
END$$
delimiter ;
Have a look into triggers: Create Trigger
Here you can react on events like inserts into a table and define respective actions for that.

Mysql Trigger will not pass last_insert_id() to connection

This is my schema:
I am trying to have an insert into "desktops" or "laptops" insert an id generated automatically from "computers". That works.
My issue is when I insert into either table, I can not select last_insert_id();
Is there something I am doing wrong? I am trying to pass the id all the way forward to my application, for further processing. Selecting MAX(id) is not a valid solution. My SQL connection makes one insert statement, and the trigger should not break that functionality...
Use test;
CREATE TABLE `laptops` (
`id` int(11) NOT NULL,
`name` varchar(45) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=innodb DEFAULT CHARSET=utf8;
CREATE TABLE `desktops` (
`id` int(11) NOT NULL,
`name` varchar(45) DEFAULT NULL,
PRIMARY KEY (`id`),
) ENGINE=innodb DEFAULT CHARSET=utf8;
CREATE TABLE `computers` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`type` varchar(45) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=innodb DEFAULT CHARSET=utf8;
CREATE TRIGGER `laptops_BINS` BEFORE INSERT ON `laptops` FOR EACH ROW
BEGIN
IF (EXISTS(SELECT id FROM laptops WHERE name = NEW.name)) THEN
SET NEW.id = NULL;
ELSE
INSERT INTO computers (type) VALUES ('laptop');
SET NEW.id = LAST_INSERT_ID();
SET NEW.id = LAST_INSERT_ID(NEW.id);
END IF;
END
CREATE TRIGGER `desktop_BINS` BEFORE INSERT ON `desktops` FOR EACH ROW
BEGIN
IF (EXISTS(SELECT id FROM desktops WHERE name = NEW.name)) THEN
SET NEW.id = NULL;
ELSE
INSERT INTO computers (type) VALUES ('desktop');
SET NEW.id = LAST_INSERT_ID();
SET NEW.id = LAST_INSERT_ID(NEW.id);
END IF;
END
INSERT INTO laptops (name) VALUES ('laptop1');
INSERT INTO laptops (desktop) VALUES ('desktop1');
INSERT INTO laptops (name) VALUES ('laptop2');
INSERT INTO laptops (desktop) VALUES ('desktop2');
SELECT last_insert_id();
Expecting 4, actually its 0.
Any thoughts as to how I can fix the trigger? Maybe someone can help me format the AFTER_INSERT statement to fix last_insert_id?
I tried setting the values to auto-increment, and unique in the laptops and desktops table, neither will fix the issue.
Rather than trying to deal with the 'confusion' of 'last_insert_id'. I decided to change the table structure to be a more 'common' format.
That is change the 'laptops' and 'desktops' tables to have the 'auto_increment' keys. This changes the 'computers' table to have a primary key of 'computer_id' from 'laptops' or 'desktops' and a 'computer_type'.
Here are the table structures and triggers.
It has been tested on mysql 5.5.16 on windows xp.
CREATE TABLE `laptops` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(45) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
CREATE TABLE `desktops` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(45) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;
CREATE TABLE `computers` (
`computer_id` int(11) NOT NULL,
`computer_type` varchar(45) NOT NULL,
PRIMARY KEY (`computer_id`,`computer_type`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
DELIMITER $$
USE `testmysql`$$
DROP TRIGGER /*!50032 IF EXISTS */ `laptop_bins`$$
CREATE
/*!50017 DEFINER = 'test'#'localhost' */
TRIGGER `laptop_bins` AFTER INSERT ON `laptops`
FOR EACH ROW BEGIN
INSERT INTO computers (computer_id, computer_type ) VALUES (new.id, 'laptop');
END;
$$
DELIMITER ;
DELIMITER $$
USE `testmysql`$$
DROP TRIGGER /*!50032 IF EXISTS */ `desktop_bins`$$
CREATE
/*!50017 DEFINER = 'test'#'localhost' */
TRIGGER `desktop_bins` AFTER INSERT ON `desktops`
FOR EACH ROW BEGIN
INSERT INTO computers (computer_id, computer_type ) VALUES (new.id, 'desktop');
END;
$$
DELIMITER ;
Sample Queries and Output:
INSERT INTO laptops (NAME) VALUES ('laptop1');
INSERT INTO desktops (NAME) VALUES ('desktop1');
INSERT INTO laptops (NAME) VALUES ('laptop2');
INSERT INTO desktops (NAME) VALUES ('desktop2');
Laptops:
id name
------ ---------
1 laptop1
2 laptop2
Desktops:
id name
------ ----------
1 desktop1
2 desktop2
Computers:
computer_id computer_type
----------- ---------------
1 desktop
1 laptop
2 desktop
2 laptop
This more a possible approach to the requirement than an answer.
I can create the code if required. It is not a lot of code on top of what is here.
The problem is to maintain tables in an other database, in sync, without doing lots of repeat work.
My suggestion:
In the 'computers' database - have a 'computers_new' table that is inserted to by the 'after insert' trigger and holds the relevant key information. Including a 'unprocessed' column.
I would then run a script at regular intervals or was triggered when the 'computers_new' table changed. It would:
1) transfer the 'unprocessed' details to the 'laptops', 'desktops' tables in the other database.
2) mark the transferred records as processed.
Advantages:
Lots of small chunks of work.
By using transactions it is reliable.
Drawbacks.
Ensuring tables are in sync.

SELECT returning no rows using declared variable inside MySQL trigger

I am trying to perform an INSERT...SELECT to create rows in a 'tasks' table once a row is created in a 'workflow' table. (The process_index used in the workflow creation looks up those tasks required in the 'process_tasks' table then creates them in the tasks table).
The problem, however, is that after performing an insert with the process_index of 'process_one' on the workflow table, the SELECT in the trigger finds no rows. I considered that the #process_id was not being set properly, but with the alternative insert i've commented out in the trigger, it demonstrates that the #process_index is being set correctly. Can anyone advise?
Here is some simplified code to demonstrate the problem:
DROP TABLE IF EXISTS workflow;
CREATE TABLE workflow (
id INT(10) PRIMARY KEY AUTO_INCREMENT,
process_index VARCHAR(12)
) ENGINE=INNODB DEFAULT CHARSET=utf8;
DROP TABLE IF EXISTS tasks;
CREATE TABLE tasks (
id INT(10) PRIMARY KEY AUTO_INCREMENT,
process_index_used VARCHAR(12),
target_field VARCHAR(12)
) ENGINE=INNODB DEFAULT CHARSET=utf8;
DROP TABLE IF EXISTS process_tasks;
CREATE TABLE process_tasks (
id INT(10) PRIMARY KEY AUTO_INCREMENT,
process_index VARCHAR(12),
source_field VARCHAR(12)
) ENGINE=INNODB DEFAULT CHARSET=utf8;
INSERT INTO process_tasks SET process_index = 'process_one', source_field = 'alpha';
INSERT INTO process_tasks SET process_index = 'process_one', source_field = 'beta';
DROP TRIGGER IF EXISTS workflow_tasks;
DELIMITER //
CREATE TRIGGER workflow_tasks AFTER INSERT ON workflow
FOR EACH ROW BEGIN
DECLARE process_index VARCHAR(12);
SET #process_index = NEW.process_index;
-- INSERT INTO tasks (process_index_used) VALUES (#process_index);
INSERT INTO tasks (target_field) SELECT source_field FROM process_tasks WHERE process_index = #process_index;
END//
DELIMITER ;