diff options
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/access/gin_private.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/src/include/access/gin_private.h b/src/include/access/gin_private.h index a136f7f9186..71eeac205c9 100644 --- a/src/include/access/gin_private.h +++ b/src/include/access/gin_private.h @@ -304,6 +304,20 @@ typedef struct GinScanKeyData OffsetNumber attnum; /* + * An excludeOnly scan key is not able to enumerate all matching tuples. + * That is, to be semantically correct on its own, it would need to have a + * GIN_CAT_EMPTY_QUERY scanEntry, but it doesn't. Such a key can still be + * used to filter tuples returned by other scan keys, so we will get the + * right answers as long as there's at least one non-excludeOnly scan key + * for each index attribute considered by the search. For efficiency + * reasons we don't want to have unnecessary GIN_CAT_EMPTY_QUERY entries, + * so we will convert an excludeOnly scan key to non-excludeOnly (by + * adding a GIN_CAT_EMPTY_QUERY scanEntry) only if there are no other + * non-excludeOnly scan keys. + */ + bool excludeOnly; + + /* * Match status data. curItem is the TID most recently tested (could be a * lossy-page pointer). curItemMatches is true if it passes the * consistentFn test; if so, recheckCurItem is the recheck flag. |