09/11: MySQL > Tips
MySQL 5.1 supports a row level replication. Before 5.1, it was a SQL statement replication, so that some functions such as UUID() were not replicated properly.
EXPLAIN (testing SQL);
MySQL does not use INDEX if you use LIKE '%...' or LIKE '_...'.
MySQL may not use INDEX if you use the result of some function.
SELECT * FROM table WHERE TO_DAYS(created_date) <= 7;
InnoDB's count(*) is much slower than MyISAM
EXPLAIN (testing SQL);
MySQL does not use INDEX if you use LIKE '%...' or LIKE '_...'.
MySQL may not use INDEX if you use the result of some function.
SELECT * FROM table WHERE TO_DAYS(created_date) <= 7;
InnoDB's count(*) is much slower than MyISAM
09/11: Linux > SSHFS
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