SQL Event - DELETE AND UPDATE rows on tables after UPDATE other table - mysql

Question

I'd like to have a tricky SQL statement as an Event that runs every couple of minutes.
Currently, I'm doing so with Java, using 3 separate statements that executing sequentiality in a transaction connection.
Q: I don't know how to construct such an SQL statement without Java. If impossible to have a single SQL statement, I'd like to use transaction (as I'm using in Java) and rollback in case of failure in any of those separate statements.
My Case:
I have 3 tables: "Factory", "Plan", "Machine".
I want to do something as below:
1.
WHERE Machines.annualCheck == "TRUE"
SET Machine.status = "IN_ANNUAL_CHECK"
For machines that got updated I need to do the following:
2.1 Update the related factory
WHERE Factory.id == Machine.linkFactoryID
UPDATE Factory.totalActiveMachines = --1
2.2 Delete the upcoming plans that planned to be handled by the related machine
DELETE rows WHERE Plan.willHandleByMachineID = Machine.ID
p.s. I'm using MySQL
Thank you!
Update:
In following to Simonare suggestion, I tired to do the following:
DELIMITER $
CREATE PROCEDURE annualCheck(IN Machine_ID int, IN Factory_ID int)
BEGIN
UPDATE machine_table
SET machine_table.annualCheck = 'IN_ANNUAL_CHECK'
WHERE machine_table.machine_id = Machine_ID;
UPDATE factory_table
SET factory_table.totalActiveMachines = factory_table.totalActiveMachines - 1
WHERE factory_table.factory_id = Factory_ID;
DELETE FROM plan_table WHERE plan_table.assign_to_machine = Machine_ID
END$
DELIMITER $$
BEGIN
SELECT #m_id = machine_id, #f_id = link_factory_id
FROM machine_table
WHERE machine_table.annualCheck = 'TRUE';
END$$
CALL annualCheck(#m_id,#f_id)
I don't know why, but I'm running into syntax errors - one after the other.
It's my first time to use PROCEDURE and DELIMITER. Am I doing it right?

Answer 1

you can use stored procedure
delimiter //
CREATE PROCEDURE myProc (IN Machine_ID int)
BEGIN
UPDATE myTable
SET Machine.status = "IN_ANNUAL_CHECK"
WHERE Machines.annualCheck == "TRUE";
Update the related factory
WHERE Factory.id == Machine.linkFactoryID
UPDATE Factory.totalActiveMachines = totalActiveMachines -1;
DELETE FROM Plan WHERE Plan.willHandleByMachineID = Machine_ID;
END//
then you can execute it either from mysql
CALL simpleproc(#a);
or from Java

Answer 2

It is also possible to create trigger on the Machine table, something like this:
CREATE TRIGGER `TRG_Machines_AfterUpdate` AFTER UPDATE ON `Machine` FOR EACH ROW BEGIN
IF OLD.annualCheck = 'TRUE' AND NEW.annualCheck = 'IN_ANNUAL_CHECK' THEN
UPDATE
Factory
SET
totalActiveMachines = totalActiveMachines - 1
WHERE
id = NEW.linkFactoryID
;
DELETE FROM
Plan
WHERE
willHandleByMachineID = NEW.ID
;
END;
END
So you can just issue normal update:
UPDATE Machine SET annualCheck = 'IN_ANNUAL_CHECK' WHERE annualCheck = 'TRUE'