how to execute a trigger everyday at once in sql - mysql

Question

we are doing a project on microbanking and we need to calculate the interest rate in database level. So we used procedures and triggers for that. but the trigger needs to execute everyday at once to perform below given procedure. Can you provide a solution to create that trigger. Thanks in advance
DELIMITER //
create procedure addFDInterestToAccount(in account_number bigint(20))
BEGIN
declare interest float default 0;
declare account_type varchar(10);
declare rate float;
declare savings_account bigint(20);
start transaction;
select balance from fd_account where account_no = account_number into interest;
SELECT plan_id from fd_account where account_no = account_number into account_type;
SELECT saving_account_no from fd_account where account_no = account_number into savings_account;
select interest_rate from fd_plan where plan_id = account_type into rate;
set interest = interest*rate/1200;
insert into transaction (transaction_id, account_no, credit_debit, date_time, amount, type_, agent_id, is_fee) values (null, savings_account, 'debit', now(), interest, 'not_special', null, false);
update account set balance = balance + interest where account_no = savings_account;
commit;
END //
DELIMITER ;
call addFDInterestToAccount(90842311);

Answer 1

As far as I understood your requirement, I think you can use SQL Events for this. The general syntax goes like this,
CREATE [OR REPLACE]
[DEFINER = { user | CURRENT_USER | role | CURRENT_ROLE }]
EVENT
[IF NOT EXISTS]
event_name
ON SCHEDULE schedule
[ON COMPLETION [NOT] PRESERVE]
[ENABLE | DISABLE | DISABLE ON SLAVE]
[COMMENT 'comment']
DO sql_statement;
schedule:
AT timestamp [+ INTERVAL interval] ...
| EVERY interval
[STARTS timestamp [+ INTERVAL interval] ...]
[ENDS timestamp [+ INTERVAL interval] ...]
interval:
quantity {YEAR | QUARTER | MONTH | DAY | HOUR | MINUTE |
WEEK | SECOND | YEAR_MONTH | DAY_HOUR | DAY_MINUTE |
DAY_SECOND | HOUR_MINUTE | HOUR_SECOND | MINUTE_SECOND}
You can modify/use following code for achiving this,
CREATE EVENT example
ON SCHEDULE EVERY 1 DAY
STARTS CURRENT_TIMESTAMP
DO call addFDInterestToAccount(90842311);
For further information you can vist the link here
Also make sure you run this query before running the event
SET GLOBAL event_scheduler = ON;

Answer 2

A trigger is defined as a procedure that runs in response to an insert, update, or delete statement. It will run every time you perform one of those DML operations. You cannot schedule a trigger to run once a day.
From the MySql documentation (but applicable to all databases that implement triggers):
A trigger is defined to activate when a statement inserts, updates, or
deletes rows in the associated table. These row operations are trigger
events.
Instead, you need to look for a task scheduler. Each OS will have its own or you could find a third-party scheduler software.