Database index
Section titled “Database index”A database index is an auxiliary data structure that maps searchable values to row locations or directly stored row data.
An index can reduce read cost when its structure matches the query. It also consumes storage and adds maintenance work to inserts, updates, and deletes.
An index is an access path available to the query planner, not a command that the planner must use.
Used in DKKB
Indexes and query planningUse indexes to turn scans into targeted lookups, and understand how the query planner decides whether an index helps.
Related knowledge
Indexes and query planningUse indexes to turn scans into targeted lookups, and understand how the query planner decides whether an index helps.