diff options
Diffstat (limited to 'src/include/nodes/plannodes.h')
| -rw-r--r-- | src/include/nodes/plannodes.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h index 1494b336c2..65f71d8170 100644 --- a/src/include/nodes/plannodes.h +++ b/src/include/nodes/plannodes.h @@ -311,8 +311,13 @@ typedef Scan SeqScan; * index column order. Only the expressions are provided, not the auxiliary * sort-order information from the ORDER BY SortGroupClauses; it's assumed * that the sort ordering is fully determinable from the top-level operators. - * indexorderbyorig is unused at run time, but is needed for EXPLAIN. - * (Note these fields are used for amcanorderbyop cases, not amcanorder cases.) + * indexorderbyorig is used at runtime to recheck the ordering, if the index + * cannot calculate an accurate ordering. It is also needed for EXPLAIN. + * + * indexorderbyops is an array of operators used to sort the ORDER BY + * expressions, used together with indexorderbyorig to recheck ordering at run + * time. (Note these fields are used for amcanorderbyop cases, not amcanorder + * cases.) * * indexorderdir specifies the scan ordering, for indexscans on amcanorder * indexes (for other indexes it should be "don't care"). @@ -326,6 +331,7 @@ typedef struct IndexScan List *indexqualorig; /* the same in original form */ List *indexorderby; /* list of index ORDER BY exprs */ List *indexorderbyorig; /* the same in original form */ + Oid *indexorderbyops; /* operators to sort ORDER BY exprs */ ScanDirection indexorderdir; /* forward or backward or don't care */ } IndexScan; |