diff options
Diffstat (limited to 'src/include/nodes/parsenodes.h')
| -rw-r--r-- | src/include/nodes/parsenodes.h | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index 1346ac8a04e..288e7f96b8d 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2000, PostgreSQL, Inc * Portions Copyright (c) 1994, Regents of the University of California * - * $Id: parsenodes.h,v 1.96 2000/01/26 05:58:16 momjian Exp $ + * $Id: parsenodes.h,v 1.97 2000/01/27 18:11:44 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -54,7 +54,8 @@ typedef struct Query Node *qual; /* qualifications applied to tuples */ List *rowMark; /* list of RowMark entries */ - char *uniqueFlag; /* NULL, '*', or Unique attribute name */ + List *distinctClause; /* a list of SortClause's */ + List *sortClause; /* a list of SortClause's */ List *groupClause; /* a list of GroupClause's */ @@ -733,7 +734,8 @@ typedef struct InsertStmt { NodeTag type; char *relname; /* relation to insert into */ - char *unique; /* NULL, '*', or unique attribute name */ + List *distinctClause; /* NULL, list of DISTINCT ON exprs, or + * lcons(NIL,NIL) for all (SELECT DISTINCT) */ List *cols; /* names of the columns */ List *targetList; /* the target list (of ResTarget) */ List *fromClause; /* the from clause */ @@ -777,7 +779,8 @@ typedef struct UpdateStmt typedef struct SelectStmt { NodeTag type; - char *unique; /* NULL, '*', or unique attribute name */ + List *distinctClause; /* NULL, list of DISTINCT ON exprs, or + * lcons(NIL,NIL) for all (SELECT DISTINCT) */ char *into; /* name of table (for select into table) */ List *targetList; /* the target list (of ResTarget) */ List *fromClause; /* the from clause */ @@ -1135,6 +1138,13 @@ typedef struct RangeTblEntry * tleSortGroupRef must match ressortgroupref of exactly one Resdom of the * associated targetlist; that is the expression to be sorted (or grouped) by. * sortop is the OID of the ordering operator. + * + * SortClauses are also used to identify Resdoms that we will do a "Unique" + * filter step on (for SELECT DISTINCT and SELECT DISTINCT ON). The + * distinctClause list is simply a copy of the relevant members of the + * sortClause list. Note that distinctClause can be a subset of sortClause, + * but cannot have members not present in sortClause; and the members that + * do appear must be in the same order as in sortClause. */ typedef struct SortClause { @@ -1148,7 +1158,7 @@ typedef struct SortClause * representation of GROUP BY clauses * * GroupClause is exactly like SortClause except for the nodetag value - * (and it's probably not even really necessary to have two different + * (it's probably not even really necessary to have two different * nodetags...). We have routines that operate interchangeably on both. */ typedef SortClause GroupClause; |