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-rw-r--r--src/backend/catalog/sql_features.txt2
-rw-r--r--src/backend/executor/nodeLimit.c160
-rw-r--r--src/backend/nodes/copyfuncs.c7
-rw-r--r--src/backend/nodes/equalfuncs.c2
-rw-r--r--src/backend/nodes/outfuncs.c7
-rw-r--r--src/backend/nodes/readfuncs.c6
-rw-r--r--src/backend/optimizer/plan/createplan.c45
-rw-r--r--src/backend/optimizer/plan/planner.c1
-rw-r--r--src/backend/optimizer/util/pathnode.c2
-rw-r--r--src/backend/parser/analyze.c21
-rw-r--r--src/backend/parser/gram.y117
-rw-r--r--src/backend/parser/parse_clause.c15
-rw-r--r--src/backend/utils/adt/ruleutils.c27
13 files changed, 352 insertions, 60 deletions
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index 3a40b027d41..b6e58e84939 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -345,7 +345,7 @@ F863 Nested <result offset clause> in <query expression> YES
F864 Top-level <result offset clause> in views YES
F865 <offset row count> in <result offset clause> YES
F866 FETCH FIRST clause: PERCENT option NO
-F867 FETCH FIRST clause: WITH TIES option NO
+F867 FETCH FIRST clause: WITH TIES option YES
R010 Row pattern recognition: FROM clause NO
R020 Row pattern recognition: WINDOW clause NO
R030 Row pattern recognition: full aggregate support NO
diff --git a/src/backend/executor/nodeLimit.c b/src/backend/executor/nodeLimit.c
index d792e97cfab..12cfc5177bb 100644
--- a/src/backend/executor/nodeLimit.c
+++ b/src/backend/executor/nodeLimit.c
@@ -41,6 +41,7 @@ static TupleTableSlot * /* return: a tuple or NULL */
ExecLimit(PlanState *pstate)
{
LimitState *node = castNode(LimitState, pstate);
+ ExprContext *econtext = node->ps.ps_ExprContext;
ScanDirection direction;
TupleTableSlot *slot;
PlanState *outerPlan;
@@ -102,6 +103,16 @@ ExecLimit(PlanState *pstate)
node->lstate = LIMIT_EMPTY;
return NULL;
}
+
+ /*
+ * Tuple at limit is needed for comparation in subsequent
+ * execution to detect ties.
+ */
+ if (node->limitOption == LIMIT_OPTION_WITH_TIES &&
+ node->position - node->offset == node->count - 1)
+ {
+ ExecCopySlot(node->last_slot, slot);
+ }
node->subSlot = slot;
if (++node->position > node->offset)
break;
@@ -125,10 +136,13 @@ ExecLimit(PlanState *pstate)
if (ScanDirectionIsForward(direction))
{
/*
- * Forwards scan, so check for stepping off end of window. If
- * we are at the end of the window, return NULL without
- * advancing the subplan or the position variable; but change
- * the state machine state to record having done so.
+ * Forwards scan, so check for stepping off end of window. At
+ * the end of the window, the behavior depends on whether WITH
+ * TIES was specified: in that case, we need to change the
+ * state machine to LIMIT_WINDOWTIES. If not (nothing was
+ * specified, or ONLY was) return NULL without advancing the
+ * subplan or the position variable but change the state
+ * machine to record having done so
*
* Once at the end, ideally, we can shut down parallel
* resources but that would destroy the parallel context which
@@ -139,12 +153,72 @@ ExecLimit(PlanState *pstate)
if (!node->noCount &&
node->position - node->offset >= node->count)
{
- node->lstate = LIMIT_WINDOWEND;
+ if (node->limitOption == LIMIT_OPTION_COUNT)
+ {
+ node->lstate = LIMIT_WINDOWEND;
+ return NULL;
+ }
+ else
+ {
+ node->lstate = LIMIT_WINDOWEND_TIES;
+ /* fall-through */
+ }
+ }
+ else
+ {
+ /*
+ * Get next tuple from subplan, if any.
+ */
+ slot = ExecProcNode(outerPlan);
+ if (TupIsNull(slot))
+ {
+ node->lstate = LIMIT_SUBPLANEOF;
+ return NULL;
+ }
+
+ /*
+ * Tuple at limit is needed for comparation in subsequent
+ * execution to detect ties.
+ */
+ if (node->limitOption == LIMIT_OPTION_WITH_TIES &&
+ node->position - node->offset == node->count - 1)
+ {
+ ExecCopySlot(node->last_slot, slot);
+ }
+ node->subSlot = slot;
+ node->position++;
+ break;
+ }
+ }
+ else
+ {
+ /*
+ * Backwards scan, so check for stepping off start of window.
+ * As above, change only state-machine status if so.
+ */
+ if (node->position <= node->offset + 1)
+ {
+ node->lstate = LIMIT_WINDOWSTART;
return NULL;
}
/*
- * Get next tuple from subplan, if any.
+ * Get previous tuple from subplan; there should be one!
+ */
+ slot = ExecProcNode(outerPlan);
+ if (TupIsNull(slot))
+ elog(ERROR, "LIMIT subplan failed to run backwards");
+ node->subSlot = slot;
+ node->position--;
+ break;
+ }
+
+ case LIMIT_WINDOWEND_TIES:
+ if (ScanDirectionIsForward(direction))
+ {
+ /*
+ * Advance the subplan until we find the first row with
+ * different ORDER BY pathkeys.
*/
slot = ExecProcNode(outerPlan);
if (TupIsNull(slot))
@@ -152,14 +226,29 @@ ExecLimit(PlanState *pstate)
node->lstate = LIMIT_SUBPLANEOF;
return NULL;
}
- node->subSlot = slot;
- node->position++;
+
+ /*
+ * Test if the new tuple and the last tuple match. If so we
+ * return the tuple.
+ */
+ econtext->ecxt_innertuple = slot;
+ econtext->ecxt_outertuple = node->last_slot;
+ if (ExecQualAndReset(node->eqfunction, econtext))
+ {
+ node->subSlot = slot;
+ node->position++;
+ }
+ else
+ {
+ node->lstate = LIMIT_WINDOWEND;
+ return NULL;
+ }
}
else
{
/*
* Backwards scan, so check for stepping off start of window.
- * As above, change only state-machine status if so.
+ * Change only state-machine status if so.
*/
if (node->position <= node->offset + 1)
{
@@ -168,13 +257,15 @@ ExecLimit(PlanState *pstate)
}
/*
- * Get previous tuple from subplan; there should be one!
+ * Get previous tuple from subplan; there should be one! And
+ * change state-machine status.
*/
slot = ExecProcNode(outerPlan);
if (TupIsNull(slot))
elog(ERROR, "LIMIT subplan failed to run backwards");
node->subSlot = slot;
node->position--;
+ node->lstate = LIMIT_INWINDOW;
}
break;
@@ -199,12 +290,28 @@ ExecLimit(PlanState *pstate)
return NULL;
/*
- * Backing up from window end: simply re-return the last tuple
- * fetched from the subplan.
+ * We already past one position to detect ties so re-fetch
+ * previous tuple; there should be one! Note previous tuple must
+ * be in window.
*/
- slot = node->subSlot;
- node->lstate = LIMIT_INWINDOW;
- /* position does not change 'cause we didn't advance it before */
+ if (node->limitOption == LIMIT_OPTION_WITH_TIES)
+ {
+ slot = ExecProcNode(outerPlan);
+ if (TupIsNull(slot))
+ elog(ERROR, "LIMIT subplan failed to run backwards");
+ node->subSlot = slot;
+ node->lstate = LIMIT_INWINDOW;
+ }
+ else
+ {
+ /*
+ * Backing up from window end: simply re-return the last tuple
+ * fetched from the subplan.
+ */
+ slot = node->subSlot;
+ node->lstate = LIMIT_INWINDOW;
+ /* position does not change 'cause we didn't advance it before */
+ }
break;
case LIMIT_WINDOWSTART:
@@ -319,7 +426,7 @@ recompute_limits(LimitState *node)
static int64
compute_tuples_needed(LimitState *node)
{
- if (node->noCount)
+ if ((node->noCount) || (node->limitOption == LIMIT_OPTION_WITH_TIES))
return -1;
/* Note: if this overflows, we'll return a negative value, which is OK */
return node->count + node->offset;
@@ -372,6 +479,7 @@ ExecInitLimit(Limit *node, EState *estate, int eflags)
(PlanState *) limitstate);
limitstate->limitCount = ExecInitExpr((Expr *) node->limitCount,
(PlanState *) limitstate);
+ limitstate->limitOption = node->limitOption;
/*
* Initialize result type.
@@ -388,6 +496,26 @@ ExecInitLimit(Limit *node, EState *estate, int eflags)
*/
limitstate->ps.ps_ProjInfo = NULL;
+ /*
+ * Initialize the equality evaluation, to detect ties.
+ */
+ if (node->limitOption == LIMIT_OPTION_WITH_TIES)
+ {
+ TupleDesc desc;
+ const TupleTableSlotOps *ops;
+
+ desc = ExecGetResultType(outerPlanState(limitstate));
+ ops = ExecGetResultSlotOps(outerPlanState(limitstate), NULL);
+
+ limitstate->last_slot = ExecInitExtraTupleSlot(estate, desc, ops);
+ limitstate->eqfunction = execTuplesMatchPrepare(desc,
+ node->uniqNumCols,
+ node->uniqColIdx,
+ node->uniqOperators,
+ node->uniqCollations,
+ &limitstate->ps);
+ }
+
return limitstate;
}
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index f9d86859ee7..1525c0de725 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -1185,6 +1185,11 @@ _copyLimit(const Limit *from)
*/
COPY_NODE_FIELD(limitOffset);
COPY_NODE_FIELD(limitCount);
+ COPY_SCALAR_FIELD(limitOption);
+ COPY_SCALAR_FIELD(uniqNumCols);
+ COPY_POINTER_FIELD(uniqColIdx, from->uniqNumCols * sizeof(AttrNumber));
+ COPY_POINTER_FIELD(uniqOperators, from->uniqNumCols * sizeof(Oid));
+ COPY_POINTER_FIELD(uniqCollations, from->uniqNumCols * sizeof(Oid));
return newnode;
}
@@ -3079,6 +3084,7 @@ _copyQuery(const Query *from)
COPY_NODE_FIELD(sortClause);
COPY_NODE_FIELD(limitOffset);
COPY_NODE_FIELD(limitCount);
+ COPY_SCALAR_FIELD(limitOption);
COPY_NODE_FIELD(rowMarks);
COPY_NODE_FIELD(setOperations);
COPY_NODE_FIELD(constraintDeps);
@@ -3163,6 +3169,7 @@ _copySelectStmt(const SelectStmt *from)
COPY_NODE_FIELD(sortClause);
COPY_NODE_FIELD(limitOffset);
COPY_NODE_FIELD(limitCount);
+ COPY_SCALAR_FIELD(limitOption);
COPY_NODE_FIELD(lockingClause);
COPY_NODE_FIELD(withClause);
COPY_SCALAR_FIELD(op);
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index e8e781834a5..4f34189ab5c 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -981,6 +981,7 @@ _equalQuery(const Query *a, const Query *b)
COMPARE_NODE_FIELD(sortClause);
COMPARE_NODE_FIELD(limitOffset);
COMPARE_NODE_FIELD(limitCount);
+ COMPARE_SCALAR_FIELD(limitOption);
COMPARE_NODE_FIELD(rowMarks);
COMPARE_NODE_FIELD(setOperations);
COMPARE_NODE_FIELD(constraintDeps);
@@ -1055,6 +1056,7 @@ _equalSelectStmt(const SelectStmt *a, const SelectStmt *b)
COMPARE_NODE_FIELD(sortClause);
COMPARE_NODE_FIELD(limitOffset);
COMPARE_NODE_FIELD(limitCount);
+ COMPARE_SCALAR_FIELD(limitOption);
COMPARE_NODE_FIELD(lockingClause);
COMPARE_NODE_FIELD(withClause);
COMPARE_SCALAR_FIELD(op);
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 35ed8c0d538..5b826509ebe 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -931,6 +931,11 @@ _outLimit(StringInfo str, const Limit *node)
WRITE_NODE_FIELD(limitOffset);
WRITE_NODE_FIELD(limitCount);
+ WRITE_ENUM_FIELD(limitOption, LimitOption);
+ WRITE_INT_FIELD(uniqNumCols);
+ WRITE_ATTRNUMBER_ARRAY(uniqColIdx, node->uniqNumCols);
+ WRITE_OID_ARRAY(uniqOperators, node->uniqNumCols);
+ WRITE_OID_ARRAY(uniqCollations, node->uniqNumCols);
}
static void
@@ -2741,6 +2746,7 @@ _outSelectStmt(StringInfo str, const SelectStmt *node)
WRITE_NODE_FIELD(sortClause);
WRITE_NODE_FIELD(limitOffset);
WRITE_NODE_FIELD(limitCount);
+ WRITE_ENUM_FIELD(limitOption, LimitOption);
WRITE_NODE_FIELD(lockingClause);
WRITE_NODE_FIELD(withClause);
WRITE_ENUM_FIELD(op, SetOperation);
@@ -2952,6 +2958,7 @@ _outQuery(StringInfo str, const Query *node)
WRITE_NODE_FIELD(sortClause);
WRITE_NODE_FIELD(limitOffset);
WRITE_NODE_FIELD(limitCount);
+ WRITE_ENUM_FIELD(limitOption, LimitOption);
WRITE_NODE_FIELD(rowMarks);
WRITE_NODE_FIELD(setOperations);
WRITE_NODE_FIELD(constraintDeps);
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 2a2f39bf047..644e0f5fc73 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -278,6 +278,7 @@ _readQuery(void)
READ_NODE_FIELD(sortClause);
READ_NODE_FIELD(limitOffset);
READ_NODE_FIELD(limitCount);
+ READ_ENUM_FIELD(limitOption, LimitOption);
READ_NODE_FIELD(rowMarks);
READ_NODE_FIELD(setOperations);
READ_NODE_FIELD(constraintDeps);
@@ -2398,6 +2399,11 @@ _readLimit(void)
READ_NODE_FIELD(limitOffset);
READ_NODE_FIELD(limitCount);
+ READ_ENUM_FIELD(limitOption, LimitOption);
+ READ_INT_FIELD(uniqNumCols);
+ READ_ATTRNUMBER_ARRAY(uniqColIdx, local_node->uniqNumCols);
+ READ_OID_ARRAY(uniqOperators, local_node->uniqNumCols);
+ READ_OID_ARRAY(uniqCollations, local_node->uniqNumCols);
READ_DONE();
}
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 6d26bfbeb5f..9941dfe65e4 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -2378,7 +2378,9 @@ create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path)
plan = (Plan *) make_limit(plan,
subparse->limitOffset,
- subparse->limitCount);
+ subparse->limitCount,
+ subparse->limitOption,
+ 0, NULL, NULL, NULL);
/* Must apply correct cost/width data to Limit node */
plan->startup_cost = mminfo->path->startup_cost;
@@ -2688,13 +2690,43 @@ create_limit_plan(PlannerInfo *root, LimitPath *best_path, int flags)
{
Limit *plan;
Plan *subplan;
+ int numUniqkeys = 0;
+ AttrNumber *uniqColIdx = NULL;
+ Oid *uniqOperators = NULL;
+ Oid *uniqCollations = NULL;
/* Limit doesn't project, so tlist requirements pass through */
subplan = create_plan_recurse(root, best_path->subpath, flags);
+ /* Extract information necessary for comparing rows for WITH TIES. */
+ if (best_path->limitOption == LIMIT_OPTION_WITH_TIES)
+ {
+ Query *parse = root->parse;
+ ListCell *l;
+
+ numUniqkeys = list_length(parse->sortClause);
+ uniqColIdx = (AttrNumber *) palloc(numUniqkeys * sizeof(AttrNumber));
+ uniqOperators = (Oid *) palloc(numUniqkeys * sizeof(Oid));
+ uniqCollations = (Oid *) palloc(numUniqkeys * sizeof(Oid));
+
+ numUniqkeys = 0;
+ foreach(l, parse->sortClause)
+ {
+ SortGroupClause *sortcl = (SortGroupClause *) lfirst(l);
+ TargetEntry *tle = get_sortgroupclause_tle(sortcl, parse->targetList);
+
+ uniqColIdx[numUniqkeys] = tle->resno;
+ uniqOperators[numUniqkeys] = sortcl->eqop;
+ uniqCollations[numUniqkeys] = exprCollation((Node *) tle->expr);
+ numUniqkeys++;
+ }
+ }
+
plan = make_limit(subplan,
best_path->limitOffset,
- best_path->limitCount);
+ best_path->limitCount,
+ best_path->limitOption,
+ numUniqkeys, uniqColIdx, uniqOperators, uniqCollations);
copy_generic_path_info(&plan->plan, (Path *) best_path);
@@ -6672,7 +6704,9 @@ make_lockrows(Plan *lefttree, List *rowMarks, int epqParam)
* Build a Limit plan node
*/
Limit *
-make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount)
+make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
+ LimitOption limitOption, int uniqNumCols, AttrNumber *uniqColIdx,
+ Oid *uniqOperators, Oid *uniqCollations)
{
Limit *node = makeNode(Limit);
Plan *plan = &node->plan;
@@ -6684,6 +6718,11 @@ make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount)
node->limitOffset = limitOffset;
node->limitCount = limitCount;
+ node->limitOption = limitOption;
+ node->uniqNumCols = uniqNumCols;
+ node->uniqColIdx = uniqColIdx;
+ node->uniqOperators = uniqOperators;
+ node->uniqCollations = uniqCollations;
return node;
}
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index a09f5e3866f..b31c52404a4 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -2319,6 +2319,7 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
path = (Path *) create_limit_path(root, final_rel, path,
parse->limitOffset,
parse->limitCount,
+ parse->limitOption,
offset_est, count_est);
}
diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c
index 4538ed88e09..e991385059f 100644
--- a/src/backend/optimizer/util/pathnode.c
+++ b/src/backend/optimizer/util/pathnode.c
@@ -3602,6 +3602,7 @@ LimitPath *
create_limit_path(PlannerInfo *root, RelOptInfo *rel,
Path *subpath,
Node *limitOffset, Node *limitCount,
+ LimitOption limitOption,
int64 offset_est, int64 count_est)
{
LimitPath *pathnode = makeNode(LimitPath);
@@ -3623,6 +3624,7 @@ create_limit_path(PlannerInfo *root, RelOptInfo *rel,
pathnode->subpath = subpath;
pathnode->limitOffset = limitOffset;
pathnode->limitCount = limitCount;
+ pathnode->limitOption = limitOption;
/*
* Adjust the output rows count and costs according to the offset/limit.
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 6676412842b..eee9c33637b 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -1281,9 +1281,12 @@ transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
/* transform LIMIT */
qry->limitOffset = transformLimitClause(pstate, stmt->limitOffset,
- EXPR_KIND_OFFSET, "OFFSET");
+ EXPR_KIND_OFFSET, "OFFSET",
+ stmt->limitOption);
qry->limitCount = transformLimitClause(pstate, stmt->limitCount,
- EXPR_KIND_LIMIT, "LIMIT");
+ EXPR_KIND_LIMIT, "LIMIT",
+ stmt->limitOption);
+ qry->limitOption = stmt->limitOption;
/* transform window clauses after we have seen all window functions */
qry->windowClause = transformWindowDefinitions(pstate,
@@ -1524,9 +1527,12 @@ transformValuesClause(ParseState *pstate, SelectStmt *stmt)
false /* allow SQL92 rules */ );
qry->limitOffset = transformLimitClause(pstate, stmt->limitOffset,
- EXPR_KIND_OFFSET, "OFFSET");
+ EXPR_KIND_OFFSET, "OFFSET",
+ stmt->limitOption);
qry->limitCount = transformLimitClause(pstate, stmt->limitCount,
- EXPR_KIND_LIMIT, "LIMIT");
+ EXPR_KIND_LIMIT, "LIMIT",
+ stmt->limitOption);
+ qry->limitOption = stmt->limitOption;
if (stmt->lockingClause)
ereport(ERROR,
@@ -1775,9 +1781,12 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
exprLocation(list_nth(qry->targetList, tllen)))));
qry->limitOffset = transformLimitClause(pstate, limitOffset,
- EXPR_KIND_OFFSET, "OFFSET");
+ EXPR_KIND_OFFSET, "OFFSET",
+ stmt->limitOption);
qry->limitCount = transformLimitClause(pstate, limitCount,
- EXPR_KIND_LIMIT, "LIMIT");
+ EXPR_KIND_LIMIT, "LIMIT",
+ stmt->limitOption);
+ qry->limitOption = stmt->limitOption;
qry->rtable = pstate->p_rtable;
qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 3449c26bd11..1219ac8c264 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -127,6 +127,14 @@ typedef struct ImportQual
List *table_names;
} ImportQual;
+/* Private struct for the result of opt_select_limit production */
+typedef struct SelectLimit
+{
+ Node *limitOffset;
+ Node *limitCount;
+ LimitOption limitOption;
+} SelectLimit;
+
/* ConstraintAttributeSpec yields an integer bitmask of these flags: */
#define CAS_NOT_DEFERRABLE 0x01
#define CAS_DEFERRABLE 0x02
@@ -164,7 +172,7 @@ static List *makeOrderedSetArgs(List *directargs, List *orderedargs,
core_yyscan_t yyscanner);
static void insertSelectOptions(SelectStmt *stmt,
List *sortClause, List *lockingClause,
- Node *limitOffset, Node *limitCount,
+ SelectLimit *limitClause,
WithClause *withClause,
core_yyscan_t yyscanner);
static Node *makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg);
@@ -242,6 +250,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
PartitionSpec *partspec;
PartitionBoundSpec *partboundspec;
RoleSpec *rolespec;
+ struct SelectLimit *selectlimit;
}
%type <node> stmt schema_stmt
@@ -374,6 +383,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%type <ival> import_qualification_type
%type <importqual> import_qualification
%type <node> vacuum_relation
+%type <selectlimit> opt_select_limit select_limit limit_clause
%type <list> stmtblock stmtmulti
OptTableElementList TableElementList OptInherit definition
@@ -394,8 +404,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
target_list opt_target_list insert_column_list set_target_list
set_clause_list set_clause
def_list operator_def_list indirection opt_indirection
- reloption_list group_clause TriggerFuncArgs select_limit
- opt_select_limit opclass_item_list opclass_drop_list
+ reloption_list group_clause TriggerFuncArgs opclass_item_list opclass_drop_list
opclass_purpose opt_opfamily transaction_mode_list_or_empty
OptTableFuncElementList TableFuncElementList opt_type_modifiers
prep_type_clause
@@ -458,7 +467,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
comment_type_any_name comment_type_name
security_label_type_any_name security_label_type_name
-%type <node> fetch_args limit_clause select_limit_value
+%type <node> fetch_args select_limit_value
offset_clause select_offset_value
select_fetch_first_value I_or_F_const
%type <ival> row_or_rows first_or_next
@@ -11378,14 +11387,14 @@ select_no_parens:
| select_clause sort_clause
{
insertSelectOptions((SelectStmt *) $1, $2, NIL,
- NULL, NULL, NULL,
+ NULL, NULL,
yyscanner);
$$ = $1;
}
| select_clause opt_sort_clause for_locking_clause opt_select_limit
{
insertSelectOptions((SelectStmt *) $1, $2, $3,
- list_nth($4, 0), list_nth($4, 1),
+ $4,
NULL,
yyscanner);
$$ = $1;
@@ -11393,7 +11402,7 @@ select_no_parens:
| select_clause opt_sort_clause select_limit opt_for_locking_clause
{
insertSelectOptions((SelectStmt *) $1, $2, $4,
- list_nth($3, 0), list_nth($3, 1),
+ $3,
NULL,
yyscanner);
$$ = $1;
@@ -11401,7 +11410,7 @@ select_no_parens:
| with_clause select_clause
{
insertSelectOptions((SelectStmt *) $2, NULL, NIL,
- NULL, NULL,
+ NULL,
$1,
yyscanner);
$$ = $2;
@@ -11409,7 +11418,7 @@ select_no_parens:
| with_clause select_clause sort_clause
{
insertSelectOptions((SelectStmt *) $2, $3, NIL,
- NULL, NULL,
+ NULL,
$1,
yyscanner);
$$ = $2;
@@ -11417,7 +11426,7 @@ select_no_parens:
| with_clause select_clause opt_sort_clause for_locking_clause opt_select_limit
{
insertSelectOptions((SelectStmt *) $2, $3, $4,
- list_nth($5, 0), list_nth($5, 1),
+ $5,
$1,
yyscanner);
$$ = $2;
@@ -11425,7 +11434,7 @@ select_no_parens:
| with_clause select_clause opt_sort_clause select_limit opt_for_locking_clause
{
insertSelectOptions((SelectStmt *) $2, $3, $5,
- list_nth($4, 0), list_nth($4, 1),
+ $4,
$1,
yyscanner);
$$ = $2;
@@ -11719,20 +11728,44 @@ sortby: a_expr USING qual_all_Op opt_nulls_order
select_limit:
- limit_clause offset_clause { $$ = list_make2($2, $1); }
- | offset_clause limit_clause { $$ = list_make2($1, $2); }
- | limit_clause { $$ = list_make2(NULL, $1); }
- | offset_clause { $$ = list_make2($1, NULL); }
+ limit_clause offset_clause
+ {
+ $$ = $1;
+ ($$)->limitOffset = $2;
+ }
+ | offset_clause limit_clause
+ {
+ $$ = $2;
+ ($$)->limitOffset = $1;
+ }
+ | limit_clause
+ {
+ $$ = $1;
+ }
+ | offset_clause
+ {
+ SelectLimit *n = (SelectLimit *) palloc(sizeof(SelectLimit));
+ n->limitOffset = $1;
+ n->limitCount = NULL;
+ n->limitOption = LIMIT_OPTION_COUNT;
+ $$ = n;
+ }
;
opt_select_limit:
select_limit { $$ = $1; }
- | /* EMPTY */ { $$ = list_make2(NULL,NULL); }
+ | /* EMPTY */ { $$ = NULL; }
;
limit_clause:
LIMIT select_limit_value
- { $$ = $2; }
+ {
+ SelectLimit *n = (SelectLimit *) palloc(sizeof(SelectLimit));
+ n->limitOffset = NULL;
+ n->limitCount = $2;
+ n->limitOption = LIMIT_OPTION_COUNT;
+ $$ = n;
+ }
| LIMIT select_limit_value ',' select_offset_value
{
/* Disabled because it was too confusing, bjm 2002-02-18 */
@@ -11750,9 +11783,29 @@ limit_clause:
* we can see the ONLY token in the lookahead slot.
*/
| FETCH first_or_next select_fetch_first_value row_or_rows ONLY
- { $$ = $3; }
+ {
+ SelectLimit *n = (SelectLimit *) palloc(sizeof(SelectLimit));
+ n->limitOffset = NULL;
+ n->limitCount = $3;
+ n->limitOption = LIMIT_OPTION_COUNT;
+ $$ = n;
+ }
+ | FETCH first_or_next select_fetch_first_value row_or_rows WITH TIES
+ {
+ SelectLimit *n = (SelectLimit *) palloc(sizeof(SelectLimit));
+ n->limitOffset = NULL;
+ n->limitCount = $3;
+ n->limitOption = LIMIT_OPTION_WITH_TIES;
+ $$ = n;
+ }
| FETCH first_or_next row_or_rows ONLY
- { $$ = makeIntConst(1, -1); }
+ {
+ SelectLimit *n = (SelectLimit *) palloc(sizeof(SelectLimit));
+ n->limitOffset = NULL;
+ n->limitCount = makeIntConst(1, -1);
+ n->limitOption = LIMIT_OPTION_COUNT;
+ $$ = n;
+ }
;
offset_clause:
@@ -16047,7 +16100,7 @@ makeOrderedSetArgs(List *directargs, List *orderedargs,
static void
insertSelectOptions(SelectStmt *stmt,
List *sortClause, List *lockingClause,
- Node *limitOffset, Node *limitCount,
+ SelectLimit *limitClause,
WithClause *withClause,
core_yyscan_t yyscanner)
{
@@ -16068,23 +16121,35 @@ insertSelectOptions(SelectStmt *stmt,
}
/* We can handle multiple locking clauses, though */
stmt->lockingClause = list_concat(stmt->lockingClause, lockingClause);
- if (limitOffset)
+ if (limitClause && limitClause->limitOffset)
{
if (stmt->limitOffset)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple OFFSET clauses not allowed"),
- parser_errposition(exprLocation(limitOffset))));
- stmt->limitOffset = limitOffset;
+ parser_errposition(exprLocation(limitClause->limitOffset))));
+ stmt->limitOffset = limitClause->limitOffset;
}
- if (limitCount)
+ if (limitClause && limitClause->limitCount)
{
if (stmt->limitCount)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("multiple LIMIT clauses not allowed"),
- parser_errposition(exprLocation(limitCount))));
- stmt->limitCount = limitCount;
+ parser_errposition(exprLocation(limitClause->limitCount))));
+ stmt->limitCount = limitClause->limitCount;
+ }
+ if (limitClause && limitClause->limitOption != LIMIT_OPTION_DEFAULT)
+ {
+ if (stmt->limitOption)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("multiple limit options not allowed")));
+ if (!stmt->sortClause && limitClause->limitOption == LIMIT_OPTION_WITH_TIES)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("WITH TIES options can not be specified without ORDER BY clause")));
+ stmt->limitOption = limitClause->limitOption;
}
if (withClause)
{
diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c
index 36a3efff876..6fff13479e4 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -1745,7 +1745,8 @@ transformWhereClause(ParseState *pstate, Node *clause,
*/
Node *
transformLimitClause(ParseState *pstate, Node *clause,
- ParseExprKind exprKind, const char *constructName)
+ ParseExprKind exprKind, const char *constructName,
+ LimitOption limitOption)
{
Node *qual;
@@ -1759,6 +1760,18 @@ transformLimitClause(ParseState *pstate, Node *clause,
/* LIMIT can't refer to any variables of the current query */
checkExprIsVarFree(pstate, qual, constructName);
+ /*
+ * Don't allow NULLs in FETCH FIRST .. WITH TIES. This test is ugly and
+ * extremely simplistic, in that you can pass a NULL anyway by hiding it
+ * inside an expression -- but this protects ruleutils against emitting an
+ * unadorned NULL that's not accepted back by the grammar.
+ */
+ if (exprKind == EXPR_KIND_LIMIT && limitOption == LIMIT_OPTION_WITH_TIES &&
+ IsA(clause, A_Const) && ((A_Const *) clause)->val.type == T_Null)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_ROW_COUNT_IN_LIMIT_CLAUSE),
+ errmsg("row count cannot be NULL in FETCH FIRST ... WITH TIES clause")));
+
return qual;
}
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index f6cf7e72a1e..695d8c32284 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -5243,7 +5243,10 @@ get_select_query_def(Query *query, deparse_context *context,
force_colno, context);
}
- /* Add the LIMIT clause if given */
+ /*
+ * Add the LIMIT/OFFSET clauses if given. If non-default options, use the
+ * standard spelling of LIMIT.
+ */
if (query->limitOffset != NULL)
{
appendContextKeyword(context, " OFFSET ",
@@ -5252,13 +5255,23 @@ get_select_query_def(Query *query, deparse_context *context,
}
if (query->limitCount != NULL)
{
- appendContextKeyword(context, " LIMIT ",
- -PRETTYINDENT_STD, PRETTYINDENT_STD, 0);
- if (IsA(query->limitCount, Const) &&
- ((Const *) query->limitCount)->constisnull)
- appendStringInfoString(buf, "ALL");
- else
+ if (query->limitOption == LIMIT_OPTION_WITH_TIES)
+ {
+ appendContextKeyword(context, " FETCH FIRST ",
+ -PRETTYINDENT_STD, PRETTYINDENT_STD, 0);
get_rule_expr(query->limitCount, context, false);
+ appendStringInfo(buf, " ROWS WITH TIES");
+ }
+ else
+ {
+ appendContextKeyword(context, " LIMIT ",
+ -PRETTYINDENT_STD, PRETTYINDENT_STD, 0);
+ if (IsA(query->limitCount, Const) &&
+ ((Const *) query->limitCount)->constisnull)
+ appendStringInfoString(buf, "ALL");
+ else
+ get_rule_expr(query->limitCount, context, false);
+ }
}
/* Add FOR [KEY] UPDATE/SHARE clauses if present */
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-04 02:36:55 +0000