Question

I have two tables with the following structure :

userid, entrydatetime, record.

tableA – has primary key (userid, entrydatetime)

tableB – has no constraints set.

I am trying to do an

INSERT INTO tableA SELECT * FROM tableB ,

but I am getting an error because tableB has all the same userid and entrydatetime.

e.g. userid = ‘12345’ and entrydatetime = ‘0000-00-00 00:00:00’.

the main data that I need from tableB are userid and record. entryDateTime is less critical to me for this scenario.

How can I merge my two tables yet keeping my tableA primary key constraint? Is there a way I can randomize or autoincrement the entrydatetime field on insert?

Answer 1

You can use following query

SET @value = CURRENT_TIMESTAMP();
INSERT INTO tableA 
(user_id, entrydatetime, record) 
(SELECT user_id, @value := @value + INTERVAL 1 SECOND, record from tableB);

Hope it helps…