mysql - information_schema tables and update_time behaviour -

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i'd have explanation information_schema , behaviours. let's want know when myisam table has been modified. write query

select update_time information_schema.tables table_schema = 'my_db' , table_name = 'my_table'

even though apply change table nothing happens in until run flush tables. unluckily seems me update_time stores date , time of moment run flush tables, not 1 when table changes occur. true? in advance.

i prefer add last_change timestamp each of tables, define "default current_timestamp on update current_timestamp", means mysql automatically update each time row modified.

with this, query table directly , know not table touched, rows touched.

it doesn't work detect deleted rows though.


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