15.9. Implementing Basic Table Scanning
The most basic storage engines implement read-only table scanning.
Such engines might be used to support SQL queries of logs and
other data files that are populated outside of MySQL.
The implementation of the methods in this section provide the
first steps toward the creation of more advanced storage engines.
The following shows the method calls made during a nine-row table
scan of the CSV
engine:
ha_tina::store_lock
ha_tina::external_lock
ha_tina::info
ha_tina::rnd_init
ha_tina::extra - ENUM HA_EXTRA_CACHE Cache record in HA_rrnd()
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::rnd_next
ha_tina::extra - ENUM HA_EXTRA_NO_CACHE End caching of records (def)
ha_tina::external_lock
ha_tina::extra - ENUM HA_EXTRA_RESET Reset database to after open