| Postgres-XC 1.1.1 Documentation | ||||
|---|---|---|---|---|
| Prev | Up | Chapter 57. GIN Indexes | Next | |
Note: The following description applies both to Postgres-XC and PostgreSQL if not described explicitly.
GIN assumes that indexable operators are strict. This
means that extractValue will not be called at all on a NULL
item value (instead, a placeholder index entry is created automatically),
and extractQuery will not be called on a NULL query
value either (instead, the query is presumed to be unsatisfiable). Note
however that NULL key values contained within a non-null composite item
or query value are supported.