How can "set timestamp" be a slow query?

mysql performance replication
Peder picture Peder · May 14, 2010 · Viewed 19k times · Source

My slow query log is full of entries like the following:

# Query_time: 1.016361  Lock_time: 0.000000 Rows_sent: 0  Rows_examined: 0
SET timestamp=1273826821;
COMMIT;

I guess the set timestamp command is issued by replication but I don't understand how set timestamp can take over a second. Any ideas of how to fix this?

Answer

newtover picture newtover · May 14, 2010

Timestamp is a data type and a built-in function in MySQL. What are you trying to achive with the following statement?

SET timestamp=1273826821;

UPD: I am sorry, I didn't know about the used MySQL hacks.

It seems that SET TIMESTAMP is used as a solution to exclude some queries from the slow log.

The OP is using the Microslow patch to enhance stat info in the slow query log, and the statement is common before statements on InnoDB tables.

Thus, the answer to OP's question is that the COMMIT statement is the slow query and not the SET TIMESTAMP.

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