Truncate table before inserting new data

Question

I'm trying to clear / empty / truncate a table in MySQL before inserting a new set of data. I think this can only be done using a trigger.

I created the following trigger:

create trigger top_destinations_truncate BEFORE INSERT
on top_destinations FOR EACH ROW
delete from top_destinations

But when I try to add a couple hundred records with my query I get this error:

HY000Can't update table 'top_destinations' in stored function/trigger because it is already used by statement which invoked this stored function/trigger.

The insert into table top_destinations query itself works fine if the trigger doesn't exist. But I need a fresh start every time...

What can I do? Maybe there is a better way in MySQL without a trigger: like a sequential type of query. First truncate, wait a little, then insert, if possible.

Answer 1

You can use a TRANSACTION, so your Table is never empty for other queries but this is not the fastest way.

START TRANSACTION;
DELETE FROM your_table;
INSERT into your_table ...
...
INSERT into your_table ....
COMMIT;

or the faster way:

TRUNCATE yout_table;
INSERT into your_table ...
...
INSERT into your_table ....

in this way the TRUNCATE deletes and recreate the table and cant be used in a TRANSACTION, but is really fast.