sql - MySQL auto increment on insert and update -


i have mysql database , need auto increment column 1 every time insert or update. if had increment column during insert have used built-in autoincrement option (usually used primary keys). how can insert , updates?

edit

sorry, posted wrong question, need increase counter 1 every time insert or update, current value of counter has stored in row being created or updated. counter starts 1 , never comes back, keep increasing "forever" (bigint). think of counter lastupdate timestamp instead of using real unix timestamps use ever increasing integer (monotonic increasing value).

p.s. i'm implementing syncronization mechanism between many local sqlite databases , 1 master mysql database behavior has implemented on both dbms.

the current state of counter can stored on separate table of course

simply use triggers.

something this:

create trigger trgiu_triggertesttable_updatecolumncountwhencolumnb    on  dbo.triggertesttable    after insert,update  begin ...

or can this:

insert tablea (firstname, lastname, logins) values ('somename', 'somelastname', 1) on duplicate key update count = count + 1;

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