Manual:Hitcounter table

The hitcounter table in MediaWiki is a temporary buffer for storage of page view information. If $wgHitcounterUpdateFreq is set to a value bigger than 1, this table stores the page_id value of every page that was visited. The value of $wgHitcounterUpdateFreq is then fed into a randomizer, which then updates the page_counter fields of the stored pages when the random number is equal to a particular value. This reduces database load; updating the page_counter field with every page hit is a main source for slow queries. After this batch update of the page_counter fields has been done, the hitcounter table is emptied.

This table was introduced in MediaWiki 1.3, and will always be empty if $wgDisableCounters is set to true. Additionally, if $wgHitcounterUpdateFreq is set to 1, the page table is directly updated, and this table is not used.

Hc_id
Contains the page_id of each visited page in the buffer.

Schema summary
DESCRIBE hitcounter in MediaWiki 1.9 and earlier gives the following: +---+--+--+-+-+---+ +---+--+--+-+-+---+ +---+--+--+-+-+---+
 * Field | Type            | Null | Key | Default | Extra |
 * hc_id | int(10) unsigned | NO  |     | NULL    |       |