Mysql changing table engine MyISAM to InnoDB

Question

On my site I have a visitor\'s table with 10 million rows.
Every request to the site inserts row to the table, in case the table is locked (usually in optimize query) v

Answer 1

oleksii.svarychevskyi is right, InnoDB uses row level locks, but if you do

ALTER TABLE table_name ENGINE = InnoDB;

to change table_name from MyIsam to InnoDB, there will be a metadata locking (at table level) because the original table engine was MyIsam.
If you try to do an UPDATE over table_name, this UPDATE will be enqueued until the ALTER TABLE ends (if you do a SHOW FULL PROCESSLIST you will see a "Waiting for table metadata lock" message associated to the UPDATE).

Answer 2

The easiest way is

ALTER TABLE table_name ENGINE = InnoDB;

If you use InnoDB engine you should not worry about locking tables, because this engine locks data by rows.