diff options
Diffstat (limited to 'src/include/nodes')
| -rw-r--r-- | src/include/nodes/parsenodes.h | 43 | ||||
| -rw-r--r-- | src/include/nodes/plannodes.h | 3 | ||||
| -rw-r--r-- | src/include/nodes/relation.h | 23 |
3 files changed, 49 insertions, 20 deletions
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index e1fe6c0ddb..d11f9ae6ea 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/nodes/parsenodes.h,v 1.337 2007/01/05 22:19:55 momjian Exp $ + * $PostgreSQL: pgsql/src/include/nodes/parsenodes.h,v 1.338 2007/01/09 02:14:15 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -36,6 +36,22 @@ typedef enum OnCommitAction ONCOMMIT_DROP /* ON COMMIT DROP */ } OnCommitAction; +/* Sort ordering options for ORDER BY and CREATE INDEX */ +typedef enum SortByDir +{ + SORTBY_DEFAULT, + SORTBY_ASC, + SORTBY_DESC, + SORTBY_USING /* not allowed in CREATE INDEX ... */ +} SortByDir; + +typedef enum SortByNulls +{ + SORTBY_NULLS_DEFAULT, + SORTBY_NULLS_FIRST, + SORTBY_NULLS_LAST +} SortByNulls; + /* * Grantable rights are encoded so that we can OR them together in a bitmask. @@ -348,14 +364,11 @@ typedef struct ResTarget /* * SortBy - for ORDER BY clause */ -#define SORTBY_ASC 1 -#define SORTBY_DESC 2 -#define SORTBY_USING 3 - typedef struct SortBy { NodeTag type; - int sortby_kind; /* see codes above */ + SortByDir sortby_dir; /* ASC/DESC/USING */ + SortByNulls sortby_nulls; /* NULLS FIRST/LAST */ List *useOp; /* name of op to use, if SORTBY_USING */ Node *node; /* expression to sort on */ } SortBy; @@ -443,6 +456,8 @@ typedef struct IndexElem char *name; /* name of attribute to index, or NULL */ Node *expr; /* expression to index, or NULL */ List *opclass; /* name of desired opclass; NIL = default */ + SortByDir ordering; /* ASC/DESC/default */ + SortByNulls nulls_ordering; /* FIRST/LAST/default */ } IndexElem; /* @@ -614,7 +629,8 @@ typedef struct RangeTblEntry * * tleSortGroupRef must match ressortgroupref of exactly one entry of the * associated targetlist; that is the expression to be sorted (or grouped) by. - * sortop is the OID of the ordering operator. + * sortop is the OID of the ordering operator (a "<" or ">" operator). + * nulls_first does about what you'd expect. * * SortClauses are also used to identify targets that we will do a "Unique" * filter step on (for SELECT DISTINCT and SELECT DISTINCT ON). The @@ -627,16 +643,21 @@ typedef struct SortClause { NodeTag type; Index tleSortGroupRef; /* reference into targetlist */ - Oid sortop; /* the sort operator to use */ + Oid sortop; /* the ordering operator ('<' op) */ + bool nulls_first; /* do NULLs come before normal values? */ } SortClause; /* * GroupClause - * representation of GROUP BY clauses * - * GroupClause is exactly like SortClause except for the nodetag value - * (it's probably not even really necessary to have two different - * nodetags...). We have routines that operate interchangeably on both. + * GroupClause is exactly like SortClause except for the nodetag value. + * We have routines that operate interchangeably on both. + * + * XXX SortClause overspecifies the semantics so far as GROUP BY is concerned + * (ditto for DISTINCT). It'd be better to specify an equality operator not + * an ordering operator. However, the two implementations are tightly entwined + * at the moment ... breaking them apart is work for another day. */ typedef SortClause GroupClause; diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h index acb73a39ed..44002a9d45 100644 --- a/src/include/nodes/plannodes.h +++ b/src/include/nodes/plannodes.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/nodes/plannodes.h,v 1.87 2007/01/05 22:19:55 momjian Exp $ + * $PostgreSQL: pgsql/src/include/nodes/plannodes.h,v 1.88 2007/01/09 02:14:15 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -385,6 +385,7 @@ typedef struct Sort int numCols; /* number of sort-key columns */ AttrNumber *sortColIdx; /* their indexes in the target list */ Oid *sortOperators; /* OIDs of operators to sort them by */ + bool *nullsFirst; /* NULLS FIRST/LAST directions */ } Sort; /* --------------- diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index 75fb572de0..4e285a765a 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.130 2007/01/05 22:19:56 momjian Exp $ + * $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.131 2007/01/09 02:14:15 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -300,19 +300,23 @@ typedef struct RelOptInfo * and indexes, but that created confusion without actually doing anything * useful. So now we have a separate IndexOptInfo struct for indexes. * - * opfamily[], indexkeys[], and ordering[] have ncolumns entries. + * opfamily[], indexkeys[], fwdsortop[], revsortop[], and nulls_first[] + * each have ncolumns entries. Note: for historical reasons, the + * opfamily array has an extra entry that is always zero. Some code + * scans until it sees a zero entry, rather than looking at ncolumns. + * * Zeroes in the indexkeys[] array indicate index columns that are * expressions; there is one element in indexprs for each such column. * - * Note: for historical reasons, the opfamily and ordering arrays have - * an extra entry that is always zero. Some code scans until it sees a - * zero entry, rather than looking at ncolumns. + * For an unordered index, the sortop arrays contains zeroes. Note that + * fwdsortop[] and nulls_first[] describe the sort ordering of a forward + * indexscan; we can also consider a backward indexscan, which will + * generate sort order described by revsortop/!nulls_first. * * The indexprs and indpred expressions have been run through * prepqual.c and eval_const_expressions() for ease of matching to - * WHERE clauses. indpred is in implicit-AND form. + * WHERE clauses. indpred is in implicit-AND form. */ - typedef struct IndexOptInfo { NodeTag type; @@ -328,7 +332,9 @@ typedef struct IndexOptInfo int ncolumns; /* number of columns in index */ Oid *opfamily; /* OIDs of operator families for columns */ int *indexkeys; /* column numbers of index's keys, or 0 */ - Oid *ordering; /* OIDs of sort operators for each column */ + Oid *fwdsortop; /* OIDs of sort operators for each column */ + Oid *revsortop; /* OIDs of sort operators for backward scan */ + bool *nulls_first; /* do NULLs come first in the sort order? */ Oid relam; /* OID of the access method (in pg_am) */ RegProcedure amcostestimate; /* OID of the access method's cost fcn */ @@ -360,6 +366,7 @@ typedef struct PathKeyItem Node *key; /* the item that is ordered */ Oid sortop; /* the ordering operator ('<' op) */ + bool nulls_first; /* do NULLs come before normal values? */ /* * key typically points to a Var node, ie a relation attribute, but it can |