diff options
Diffstat (limited to 'src/backend/parser')
| -rw-r--r-- | src/backend/parser/Makefile | 2 | ||||
| -rw-r--r-- | src/backend/parser/analyze.c | 18 | ||||
| -rw-r--r-- | src/backend/parser/gram.y | 151 | ||||
| -rw-r--r-- | src/backend/parser/parse_agg.c | 10 | ||||
| -rw-r--r-- | src/backend/parser/parse_clause.c | 57 | ||||
| -rw-r--r-- | src/backend/parser/parse_collate.c | 1 | ||||
| -rw-r--r-- | src/backend/parser/parse_expr.c | 3 | ||||
| -rw-r--r-- | src/backend/parser/parse_func.c | 3 | ||||
| -rw-r--r-- | src/backend/parser/parse_merge.c | 654 | ||||
| -rw-r--r-- | src/backend/parser/parse_relation.c | 10 |
10 files changed, 21 insertions, 888 deletions
diff --git a/src/backend/parser/Makefile b/src/backend/parser/Makefile index 95fdf0b9732..f14febdbda0 100644 --- a/src/backend/parser/Makefile +++ b/src/backend/parser/Makefile @@ -14,7 +14,7 @@ override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS) OBJS= analyze.o gram.o scan.o parser.o \ parse_agg.o parse_clause.o parse_coerce.o parse_collate.o parse_cte.o \ - parse_enr.o parse_expr.o parse_func.o parse_merge.o parse_node.o parse_oper.o \ + parse_enr.o parse_expr.o parse_func.o parse_node.o parse_oper.o \ parse_param.o parse_relation.o parse_target.o parse_type.o \ parse_utilcmd.o scansup.o diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c index 606021bc94f..0c66ea1dfce 100644 --- a/src/backend/parser/analyze.c +++ b/src/backend/parser/analyze.c @@ -38,7 +38,6 @@ #include "parser/parse_cte.h" #include "parser/parse_expr.h" #include "parser/parse_func.h" -#include "parser/parse_merge.h" #include "parser/parse_oper.h" #include "parser/parse_param.h" #include "parser/parse_relation.h" @@ -54,6 +53,9 @@ post_parse_analyze_hook_type post_parse_analyze_hook = NULL; static Query *transformOptionalSelectInto(ParseState *pstate, Node *parseTree); static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt); static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt); +static List *transformInsertRow(ParseState *pstate, List *exprlist, + List *stmtcols, List *icolumns, List *attrnos, + bool strip_indirection); static OnConflictExpr *transformOnConflictClause(ParseState *pstate, OnConflictClause *onConflictClause); static int count_rowexpr_columns(ParseState *pstate, Node *expr); @@ -66,6 +68,8 @@ static void determineRecursiveColTypes(ParseState *pstate, Node *larg, List *nrtargetlist); static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt); static List *transformReturningList(ParseState *pstate, List *returningList); +static List *transformUpdateTargetList(ParseState *pstate, + List *targetList); static Query *transformDeclareCursorStmt(ParseState *pstate, DeclareCursorStmt *stmt); static Query *transformExplainStmt(ParseState *pstate, @@ -263,7 +267,6 @@ transformStmt(ParseState *pstate, Node *parseTree) case T_InsertStmt: case T_UpdateStmt: case T_DeleteStmt: - case T_MergeStmt: (void) test_raw_expression_coverage(parseTree, NULL); break; default: @@ -288,10 +291,6 @@ transformStmt(ParseState *pstate, Node *parseTree) result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree); break; - case T_MergeStmt: - result = transformMergeStmt(pstate, (MergeStmt *) parseTree); - break; - case T_SelectStmt: { SelectStmt *n = (SelectStmt *) parseTree; @@ -367,7 +366,6 @@ analyze_requires_snapshot(RawStmt *parseTree) case T_InsertStmt: case T_DeleteStmt: case T_UpdateStmt: - case T_MergeStmt: case T_SelectStmt: result = true; break; @@ -898,7 +896,7 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt) * attrnos: integer column numbers (must be same length as icolumns) * strip_indirection: if true, remove any field/array assignment nodes */ -List * +static List * transformInsertRow(ParseState *pstate, List *exprlist, List *stmtcols, List *icolumns, List *attrnos, bool strip_indirection) @@ -2262,9 +2260,9 @@ transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt) /* * transformUpdateTargetList - - * handle SET clause in UPDATE/MERGE/INSERT ... ON CONFLICT UPDATE + * handle SET clause in UPDATE/INSERT ... ON CONFLICT UPDATE */ -List * +static List * transformUpdateTargetList(ParseState *pstate, List *origTlist) { List *tlist = NIL; diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index dd0c26c11b8..e5484766234 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -241,7 +241,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); PartitionSpec *partspec; PartitionBoundSpec *partboundspec; RoleSpec *rolespec; - MergeWhenClause *mergewhen; } %type <node> stmt schema_stmt @@ -283,7 +282,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); CreateMatViewStmt RefreshMatViewStmt CreateAmStmt CreatePublicationStmt AlterPublicationStmt CreateSubscriptionStmt AlterSubscriptionStmt DropSubscriptionStmt - MergeStmt %type <node> select_no_parens select_with_parens select_clause simple_select values_clause @@ -402,7 +400,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); TriggerTransitions TriggerReferencing publication_name_list vacuum_relation_list opt_vacuum_relation_list - merge_values_clause %type <list> group_by_list %type <node> group_by_item empty_grouping_set rollup_clause cube_clause @@ -463,7 +460,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); %type <istmt> insert_rest %type <infer> opt_conf_expr %type <onconflict> opt_on_conflict -%type <mergewhen> merge_insert merge_update merge_delete %type <vsetstmt> generic_set set_rest set_rest_more generic_reset reset_rest SetResetClause FunctionSetResetClause @@ -589,9 +585,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); %type <list> hash_partbound partbound_datum_list range_datum_list %type <defelt> hash_partbound_elem -%type <node> merge_when_clause opt_merge_when_and_condition -%type <list> merge_when_list - /* * Non-keyword token types. These are hard-wired into the "flex" lexer. * They must be listed first so that their numeric codes do not depend on @@ -659,8 +652,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); LEADING LEAKPROOF LEAST LEFT LEVEL LIKE LIMIT LISTEN LOAD LOCAL LOCALTIME LOCALTIMESTAMP LOCATION LOCK_P LOCKED LOGGED - MAPPING MATCH MATCHED MATERIALIZED MAXVALUE MERGE METHOD - MINUTE_P MINVALUE MODE MONTH_P MOVE + MAPPING MATCH MATERIALIZED MAXVALUE METHOD MINUTE_P MINVALUE MODE MONTH_P MOVE NAME_P NAMES NATIONAL NATURAL NCHAR NEW NEXT NO NONE NOT NOTHING NOTIFY NOTNULL NOWAIT NULL_P NULLIF @@ -929,7 +921,6 @@ stmt : | RefreshMatViewStmt | LoadStmt | LockStmt - | MergeStmt | NotifyStmt | PrepareStmt | ReassignOwnedStmt @@ -10689,7 +10680,6 @@ ExplainableStmt: | InsertStmt | UpdateStmt | DeleteStmt - | MergeStmt | DeclareCursorStmt | CreateAsStmt | CreateMatViewStmt @@ -10752,7 +10742,6 @@ PreparableStmt: | InsertStmt | UpdateStmt | DeleteStmt /* by default all are $$=$1 */ - | MergeStmt ; /***************************************************************************** @@ -11122,142 +11111,6 @@ set_target_list: /***************************************************************************** * * QUERY: - * MERGE STATEMENTS - * - *****************************************************************************/ - -MergeStmt: - opt_with_clause MERGE INTO relation_expr_opt_alias - USING table_ref - ON a_expr - merge_when_list - { - MergeStmt *m = makeNode(MergeStmt); - - m->withClause = $1; - m->relation = $4; - m->source_relation = $6; - m->join_condition = $8; - m->mergeWhenClauses = $9; - - $$ = (Node *)m; - } - ; - - -merge_when_list: - merge_when_clause { $$ = list_make1($1); } - | merge_when_list merge_when_clause { $$ = lappend($1,$2); } - ; - -merge_when_clause: - WHEN MATCHED opt_merge_when_and_condition THEN merge_update - { - $5->matched = true; - $5->commandType = CMD_UPDATE; - $5->condition = $3; - - $$ = (Node *) $5; - } - | WHEN MATCHED opt_merge_when_and_condition THEN merge_delete - { - MergeWhenClause *m = makeNode(MergeWhenClause); - - m->matched = true; - m->commandType = CMD_DELETE; - m->condition = $3; - - $$ = (Node *)m; - } - | WHEN NOT MATCHED opt_merge_when_and_condition THEN merge_insert - { - $6->matched = false; - $6->commandType = CMD_INSERT; - $6->condition = $4; - - $$ = (Node *) $6; - } - | WHEN NOT MATCHED opt_merge_when_and_condition THEN DO NOTHING - { - MergeWhenClause *m = makeNode(MergeWhenClause); - - m->matched = false; - m->commandType = CMD_NOTHING; - m->condition = $4; - - $$ = (Node *)m; - } - ; - -opt_merge_when_and_condition: - AND a_expr { $$ = $2; } - | { $$ = NULL; } - ; - -merge_delete: - DELETE_P { $$ = NULL; } - ; - -merge_update: - UPDATE SET set_clause_list - { - MergeWhenClause *n = makeNode(MergeWhenClause); - n->targetList = $3; - - $$ = n; - } - ; - -merge_insert: - INSERT merge_values_clause - { - MergeWhenClause *n = makeNode(MergeWhenClause); - n->cols = NIL; - n->values = $2; - $$ = n; - } - | INSERT OVERRIDING override_kind VALUE_P merge_values_clause - { - MergeWhenClause *n = makeNode(MergeWhenClause); - n->cols = NIL; - n->override = $3; - n->values = $5; - $$ = n; - } - | INSERT '(' insert_column_list ')' merge_values_clause - { - MergeWhenClause *n = makeNode(MergeWhenClause); - n->cols = $3; - n->values = $5; - $$ = n; - } - | INSERT '(' insert_column_list ')' OVERRIDING override_kind VALUE_P merge_values_clause - { - MergeWhenClause *n = makeNode(MergeWhenClause); - n->cols = $3; - n->override = $6; - n->values = $8; - $$ = n; - } - | INSERT DEFAULT VALUES - { - MergeWhenClause *n = makeNode(MergeWhenClause); - n->cols = NIL; - n->values = NIL; - $$ = n; - } - ; - -merge_values_clause: - VALUES '(' expr_list ')' - { - $$ = $3; - } - ; - -/***************************************************************************** - * - * QUERY: * CURSOR STATEMENTS * *****************************************************************************/ @@ -15256,10 +15109,8 @@ unreserved_keyword: | LOGGED | MAPPING | MATCH - | MATCHED | MATERIALIZED | MAXVALUE - | MERGE | METHOD | MINUTE_P | MINVALUE diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c index 0307738946a..61727e1d71a 100644 --- a/src/backend/parser/parse_agg.c +++ b/src/backend/parser/parse_agg.c @@ -455,13 +455,6 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr) case EXPR_KIND_VALUES_SINGLE: errkind = true; break; - case EXPR_KIND_MERGE_WHEN_AND: - if (isAgg) - err = _("aggregate functions are not allowed in WHEN AND conditions"); - else - err = _("grouping operations are not allowed in WHEN AND conditions"); - - break; case EXPR_KIND_CHECK_CONSTRAINT: case EXPR_KIND_DOMAIN_CHECK: if (isAgg) @@ -880,9 +873,6 @@ transformWindowFuncCall(ParseState *pstate, WindowFunc *wfunc, case EXPR_KIND_VALUES_SINGLE: errkind = true; break; - case EXPR_KIND_MERGE_WHEN_AND: - err = _("window functions are not allowed in WHEN AND conditions"); - break; case EXPR_KIND_CHECK_CONSTRAINT: case EXPR_KIND_DOMAIN_CHECK: err = _("window functions are not allowed in check constraints"); diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c index c73d06b3917..e1478805c26 100644 --- a/src/backend/parser/parse_clause.c +++ b/src/backend/parser/parse_clause.c @@ -76,6 +76,9 @@ static RangeTblEntry *transformRangeTableFunc(ParseState *pstate, RangeTableFunc *t); static TableSampleClause *transformRangeTableSample(ParseState *pstate, RangeTableSample *rts); +static Node *transformFromClauseItem(ParseState *pstate, Node *n, + RangeTblEntry **top_rte, int *top_rti, + List **namespace); static Node *buildMergedJoinVar(ParseState *pstate, JoinType jointype, Var *l_colvar, Var *r_colvar); static ParseNamespaceItem *makeNamespaceItem(RangeTblEntry *rte, @@ -136,7 +139,6 @@ transformFromClause(ParseState *pstate, List *frmList) n = transformFromClauseItem(pstate, n, &rte, &rtindex, - NULL, NULL, &namespace); checkNameSpaceConflicts(pstate, pstate->p_namespace, namespace); @@ -1094,21 +1096,14 @@ getRTEForSpecialRelationTypes(ParseState *pstate, RangeVar *rv) * * *top_rti: receives the rangetable index of top_rte. (Ditto.) * - * *right_rte: receives the RTE corresponding to the right side of the - * jointree. Only MERGE really needs to know about this and only MERGE passes a - * non-NULL pointer. - * - * *right_rti: receives the rangetable index of the right_rte. - * * *namespace: receives a List of ParseNamespaceItems for the RTEs exposed * as table/column names by this item. (The lateral_only flags in these items * are indeterminate and should be explicitly set by the caller before use.) */ -Node * +static Node * transformFromClauseItem(ParseState *pstate, Node *n, RangeTblEntry **top_rte, int *top_rti, - RangeTblEntry **right_rte, int *right_rti, - List **fnamespace) + List **namespace) { if (IsA(n, RangeVar)) { @@ -1130,7 +1125,7 @@ transformFromClauseItem(ParseState *pstate, Node *n, Assert(rte == rt_fetch(rtindex, pstate->p_rtable)); *top_rte = rte; *top_rti = rtindex; - *fnamespace = list_make1(makeDefaultNSItem(rte)); + *namespace = list_make1(makeDefaultNSItem(rte)); rtr = makeNode(RangeTblRef); rtr->rtindex = rtindex; return (Node *) rtr; @@ -1148,7 +1143,7 @@ transformFromClauseItem(ParseState *pstate, Node *n, Assert(rte == rt_fetch(rtindex, pstate->p_rtable)); *top_rte = rte; *top_rti = rtindex; - *fnamespace = list_make1(makeDefaultNSItem(rte)); + *namespace = list_make1(makeDefaultNSItem(rte)); rtr = makeNode(RangeTblRef); rtr->rtindex = rtindex; return (Node *) rtr; @@ -1166,7 +1161,7 @@ transformFromClauseItem(ParseState *pstate, Node *n, Assert(rte == rt_fetch(rtindex, pstate->p_rtable)); *top_rte = rte; *top_rti = rtindex; - *fnamespace = list_make1(makeDefaultNSItem(rte)); + *namespace = list_make1(makeDefaultNSItem(rte)); rtr = makeNode(RangeTblRef); rtr->rtindex = rtindex; return (Node *) rtr; @@ -1184,7 +1179,7 @@ transformFromClauseItem(ParseState *pstate, Node *n, Assert(rte == rt_fetch(rtindex, pstate->p_rtable)); *top_rte = rte; *top_rti = rtindex; - *fnamespace = list_make1(makeDefaultNSItem(rte)); + *namespace = list_make1(makeDefaultNSItem(rte)); rtr = makeNode(RangeTblRef); rtr->rtindex = rtindex; return (Node *) rtr; @@ -1199,7 +1194,7 @@ transformFromClauseItem(ParseState *pstate, Node *n, /* Recursively transform the contained relation */ rel = transformFromClauseItem(pstate, rts->relation, - top_rte, top_rti, NULL, NULL, fnamespace); + top_rte, top_rti, namespace); /* Currently, grammar could only return a RangeVar as contained rel */ rtr = castNode(RangeTblRef, rel); rte = rt_fetch(rtr->rtindex, pstate->p_rtable); @@ -1227,7 +1222,6 @@ transformFromClauseItem(ParseState *pstate, Node *n, List *l_namespace, *r_namespace, *my_namespace, - *save_namespace, *l_colnames, *r_colnames, *res_colnames, @@ -1246,7 +1240,6 @@ transformFromClauseItem(ParseState *pstate, Node *n, j->larg = transformFromClauseItem(pstate, j->larg, &l_rte, &l_rtindex, - NULL, NULL, &l_namespace); /* @@ -1270,34 +1263,12 @@ transformFromClauseItem(ParseState *pstate, Node *n, sv_namespace_length = list_length(pstate->p_namespace); pstate->p_namespace = list_concat(pstate->p_namespace, l_namespace); - /* - * If we are running MERGE, don't make the other RTEs visible while - * parsing the source relation. It mustn't see them. - * - * Currently, only MERGE passes non-NULL value for right_rte, so we - * can safely deduce if we're running MERGE or not by just looking at - * the right_rte. If that ever changes, we should look at other means - * to find that. - */ - if (right_rte) - { - save_namespace = pstate->p_namespace; - pstate->p_namespace = NIL; - } - /* And now we can process the RHS */ j->rarg = transformFromClauseItem(pstate, j->rarg, &r_rte, &r_rtindex, - NULL, NULL, &r_namespace); - /* - * And now restore the namespace again so that join-quals can see it. - */ - if (right_rte) - pstate->p_namespace = save_namespace; - /* Remove the left-side RTEs from the namespace list again */ pstate->p_namespace = list_truncate(pstate->p_namespace, sv_namespace_length); @@ -1324,12 +1295,6 @@ transformFromClauseItem(ParseState *pstate, Node *n, expandRTE(r_rte, r_rtindex, 0, -1, false, &r_colnames, &r_colvars); - if (right_rte) - *right_rte = r_rte; - - if (right_rti) - *right_rti = r_rtindex; - /* * Natural join does not explicitly specify columns; must generate * columns to join. Need to run through the list of columns from each @@ -1558,7 +1523,7 @@ transformFromClauseItem(ParseState *pstate, Node *n, * The join RTE itself is always made visible for unqualified column * names. It's visible as a relation name only if it has an alias. */ - *fnamespace = lappend(my_namespace, + *namespace = lappend(my_namespace, makeNamespaceItem(rte, (j->alias != NULL), true, diff --git a/src/backend/parser/parse_collate.c b/src/backend/parser/parse_collate.c index 51c73c4018a..6d34245083e 100644 --- a/src/backend/parser/parse_collate.c +++ b/src/backend/parser/parse_collate.c @@ -485,7 +485,6 @@ assign_collations_walker(Node *node, assign_collations_context *context) case T_FromExpr: case T_OnConflictExpr: case T_SortGroupClause: - case T_MergeAction: (void) expression_tree_walker(node, assign_collations_walker, (void *) &loccontext); diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c index 38fbe3366fc..385e54a9b69 100644 --- a/src/backend/parser/parse_expr.c +++ b/src/backend/parser/parse_expr.c @@ -1818,7 +1818,6 @@ transformSubLink(ParseState *pstate, SubLink *sublink) case EXPR_KIND_RETURNING: case EXPR_KIND_VALUES: case EXPR_KIND_VALUES_SINGLE: - case EXPR_KIND_MERGE_WHEN_AND: /* okay */ break; case EXPR_KIND_CHECK_CONSTRAINT: @@ -3476,8 +3475,6 @@ ParseExprKindName(ParseExprKind exprKind) return "PARTITION BY"; case EXPR_KIND_CALL_ARGUMENT: return "CALL"; - case EXPR_KIND_MERGE_WHEN_AND: - return "MERGE WHEN AND"; /* * There is intentionally no default: case here, so that the diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c index 615aee6d15f..ea5d5212b4c 100644 --- a/src/backend/parser/parse_func.c +++ b/src/backend/parser/parse_func.c @@ -2277,9 +2277,6 @@ check_srf_call_placement(ParseState *pstate, Node *last_srf, int location) /* okay, since we process this like a SELECT tlist */ pstate->p_hasTargetSRFs = true; break; - case EXPR_KIND_MERGE_WHEN_AND: - err = _("set-returning functions are not allowed in WHEN AND conditions"); - break; case EXPR_KIND_CHECK_CONSTRAINT: case EXPR_KIND_DOMAIN_CHECK: err = _("set-returning functions are not allowed in check constraints"); diff --git a/src/backend/parser/parse_merge.c b/src/backend/parser/parse_merge.c deleted file mode 100644 index 722cb23b86c..00000000000 --- a/src/backend/parser/parse_merge.c +++ /dev/null @@ -1,654 +0,0 @@ -/*------------------------------------------------------------------------- - * - * parse_merge.c - * handle merge-statement in parser - * - * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group - * Portions Copyright (c) 1994, Regents of the University of California - * - * - * IDENTIFICATION - * src/backend/parser/parse_merge.c - * - *------------------------------------------------------------------------- - */ - -#include "postgres.h" - -#include "miscadmin.h" - -#include "access/sysattr.h" -#include "nodes/makefuncs.h" -#include "parser/analyze.h" -#include "parser/parse_collate.h" -#include "parser/parsetree.h" -#include "parser/parser.h" -#include "parser/parse_clause.h" -#include "parser/parse_cte.h" -#include "parser/parse_merge.h" -#include "parser/parse_relation.h" -#include "parser/parse_target.h" -#include "utils/rel.h" -#include "utils/relcache.h" - -static int transformMergeJoinClause(ParseState *pstate, Node *merge, - List **mergeSourceTargetList); -static void setNamespaceForMergeWhen(ParseState *pstate, - MergeWhenClause *mergeWhenClause); -static void setNamespaceVisibilityForRTE(List *namespace, RangeTblEntry *rte, - bool rel_visible, - bool cols_visible); -static List *expandSourceTL(ParseState *pstate, RangeTblEntry *rte, - int rtindex); - -/* - * Special handling for MERGE statement is required because we assemble - * the query manually. This is similar to setTargetTable() followed - * by transformFromClause() but with a few less steps. - * - * Process the FROM clause and add items to the query's range table, - * joinlist, and namespace. - * - * A special targetlist comprising of the columns from the right-subtree of - * the join is populated and returned. Note that when the JoinExpr is - * setup by transformMergeStmt, the left subtree has the target result - * relation and the right subtree has the source relation. - * - * Returns the rangetable index of the target relation. - */ -static int -transformMergeJoinClause(ParseState *pstate, Node *merge, - List **mergeSourceTargetList) -{ - RangeTblEntry *rte, - *rt_rte; - List *namespace; - int rtindex, - rt_rtindex; - Node *n; - int mergeTarget_relation = list_length(pstate->p_rtable) + 1; - Var *var; - TargetEntry *te; - - n = transformFromClauseItem(pstate, merge, - &rte, - &rtindex, - &rt_rte, - &rt_rtindex, - &namespace); - - pstate->p_joinlist = list_make1(n); - - /* - * We created an internal join between the target and the source relation - * to carry out the MERGE actions. Normally such an unaliased join hides - * the joining relations, unless the column references are qualified. - * Also, any unqualified column references are resolved to the Join RTE, if - * there is a matching entry in the targetlist. But the way MERGE - * execution is later setup, we expect all column references to resolve to - * either the source or the target relation. Hence we must not add the - * Join RTE to the namespace. - * - * The last entry must be for the top-level Join RTE. We don't want to - * resolve any references to the Join RTE. So discard that. - * - * We also do not want to resolve any references from the leftside of the - * Join since that corresponds to the target relation. References to the - * columns of the target relation must be resolved from the result - * relation and not the one that is used in the join. So the - * mergeTarget_relation is marked invisible to both qualified as well as - * unqualified references. - */ - Assert(list_length(namespace) > 1); - namespace = list_truncate(namespace, list_length(namespace) - 1); - pstate->p_namespace = list_concat(pstate->p_namespace, namespace); - - setNamespaceVisibilityForRTE(pstate->p_namespace, - rt_fetch(mergeTarget_relation, pstate->p_rtable), false, false); - - /* - * Expand the right relation and add its columns to the - * mergeSourceTargetList. Note that the right relation can either be a - * plain relation or a subquery or anything that can have a - * RangeTableEntry. - */ - *mergeSourceTargetList = expandSourceTL(pstate, rt_rte, rt_rtindex); - - /* - * Add a whole-row-Var entry to support references to "source.*". - */ - var = makeWholeRowVar(rt_rte, rt_rtindex, 0, false); - te = makeTargetEntry((Expr *) var, list_length(*mergeSourceTargetList) + 1, - NULL, true); - *mergeSourceTargetList = lappend(*mergeSourceTargetList, te); - - return mergeTarget_relation; -} - -/* - * Make appropriate changes to the namespace visibility while transforming - * individual action's quals and targetlist expressions. In particular, for - * INSERT actions we must only see the source relation (since INSERT action is - * invoked for NOT MATCHED tuples and hence there is no target tuple to deal - * with). On the other hand, UPDATE and DELETE actions can see both source and - * target relations. - * - * Also, since the internal Join node can hide the source and target - * relations, we must explicitly make the respective relation as visible so - * that columns can be referenced unqualified from these relations. - */ -static void -setNamespaceForMergeWhen(ParseState *pstate, MergeWhenClause *mergeWhenClause) -{ - RangeTblEntry *targetRelRTE, - *sourceRelRTE; - - /* Assume target relation is at index 1 */ - targetRelRTE = rt_fetch(1, pstate->p_rtable); - - /* - * Assume that the top-level join RTE is at the end. The source relation - * is just before that. - */ - sourceRelRTE = rt_fetch(list_length(pstate->p_rtable) - 1, pstate->p_rtable); - - switch (mergeWhenClause->commandType) - { - case CMD_INSERT: - - /* - * Inserts can't see target relation, but they can see source - * relation. - */ - setNamespaceVisibilityForRTE(pstate->p_namespace, - targetRelRTE, false, false); - setNamespaceVisibilityForRTE(pstate->p_namespace, - sourceRelRTE, true, true); - break; - - case CMD_UPDATE: - case CMD_DELETE: - - /* - * Updates and deletes can see both target and source relations. - */ - setNamespaceVisibilityForRTE(pstate->p_namespace, - targetRelRTE, true, true); - setNamespaceVisibilityForRTE(pstate->p_namespace, - sourceRelRTE, true, true); - break; - - case CMD_NOTHING: - break; - default: - elog(ERROR, "unknown action in MERGE WHEN clause"); - } -} - -/* - * transformMergeStmt - - * transforms a MERGE statement - */ -Query * -transformMergeStmt(ParseState *pstate, MergeStmt *stmt) -{ - Query *qry = makeNode(Query); - ListCell *l; - AclMode targetPerms = ACL_NO_RIGHTS; - bool is_terminal[2]; - JoinExpr *joinexpr; - RangeTblEntry *resultRelRTE, *mergeRelRTE; - List *mergeActionList; - - /* There can't be any outer WITH to worry about */ - Assert(pstate->p_ctenamespace == NIL); - - qry->commandType = CMD_MERGE; - qry->hasRecursive = false; - - /* process the WITH clause independently of all else */ - if (stmt->withClause) - { - if (stmt->withClause->recursive) - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - errmsg("WITH RECURSIVE is not supported for MERGE statement"))); - - qry->cteList = transformWithClause(pstate, stmt->withClause); - qry->hasModifyingCTE = pstate->p_hasModifyingCTE; - } - - /* - * Check WHEN clauses for permissions and sanity - */ - is_terminal[0] = false; - is_terminal[1] = false; - foreach(l, stmt->mergeWhenClauses) - { - MergeWhenClause *mergeWhenClause = (MergeWhenClause *) lfirst(l); - int when_type = (mergeWhenClause->matched ? 0 : 1); - - /* - * Collect action types so we can check Target permissions - */ - switch (mergeWhenClause->commandType) - { - case CMD_INSERT: - targetPerms |= ACL_INSERT; - break; - case CMD_UPDATE: - targetPerms |= ACL_UPDATE; - break; - case CMD_DELETE: - targetPerms |= ACL_DELETE; - break; - case CMD_NOTHING: - break; - default: - elog(ERROR, "unknown action in MERGE WHEN clause"); - } - - /* - * Check for unreachable WHEN clauses - */ - if (mergeWhenClause->condition == NULL) - is_terminal[when_type] = true; - else if (is_terminal[when_type]) - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - errmsg("unreachable WHEN clause specified after unconditional WHEN clause"))); - } - - /* - * Construct a query of the form - * SELECT relation.ctid --junk attribute - * ,relation.tableoid --junk attribute - * ,source_relation.<somecols> - * ,relation.<somecols> - * FROM relation RIGHT JOIN source_relation - * ON join_condition; -- no WHERE clause - all conditions are applied in - * executor - * - * stmt->relation is the target relation, given as a RangeVar - * stmt->source_relation is a RangeVar or subquery - * - * We specify the join as a RIGHT JOIN as a simple way of forcing the - * first (larg) RTE to refer to the target table. - * - * The MERGE query's join can be tuned in some cases, see below for these - * special case tweaks. - * - * We set QSRC_PARSER to show query constructed in parse analysis - * - * Note that we have only one Query for a MERGE statement and the planner - * is called only once. That query is executed once to produce our stream - * of candidate change rows, so the query must contain all of the columns - * required by each of the targetlist or conditions for each action. - * - * As top-level statements INSERT, UPDATE and DELETE have a Query, whereas - * with MERGE the individual actions do not require separate planning, - * only different handling in the executor. See nodeModifyTable handling - * of commandType CMD_MERGE. - * - * A sub-query can include the Target, but otherwise the sub-query cannot - * reference the outermost Target table at all. - */ - qry->querySource = QSRC_PARSER; - - /* - * Setup the target table. Unlike regular UPDATE/DELETE, we don't expand - * inheritance for the target relation in case of MERGE. - * - * This special arrangement is required for handling partitioned tables - * because we perform an JOIN between the target and the source relation to - * identify the matching and not-matching rows. If we take the usual path - * of expanding the target table's inheritance and create one subplan per - * partition, then we we won't be able to correctly identify the matching - * and not-matching rows since for a given source row, there may not be a - * matching row in one partition, but it may exists in some other - * partition. So we must first append all the qualifying rows from all the - * partitions and then do the matching. - * - * Once a target row is returned by the underlying join, we find the - * correct partition and setup required state to carry out UPDATE/DELETE. - * All of this happens during execution. - */ - qry->resultRelation = setTargetTable(pstate, stmt->relation, - false, /* do not expand inheritance */ - true, targetPerms); - - /* - * Create a JOIN between the target and the source relation. - */ - joinexpr = makeNode(JoinExpr); - joinexpr->isNatural = false; - joinexpr->alias = NULL; - joinexpr->usingClause = NIL; - joinexpr->quals = stmt->join_condition; - joinexpr->larg = (Node *) stmt->relation; - joinexpr->rarg = (Node *) stmt->source_relation; - - /* - * Simplify the MERGE query as much as possible - * - * These seem like things that could go into Optimizer, but they are - * semantic simplifications rather than optimizations, per se. - * - * If there are no INSERT actions we won't be using the non-matching - * candidate rows for anything, so no need for an outer join. We do still - * need an inner join for UPDATE and DELETE actions. - */ - if (targetPerms & ACL_INSERT) - joinexpr->jointype = JOIN_RIGHT; - else - joinexpr->jointype = JOIN_INNER; - - /* - * We use a special purpose transformation here because the normal - * routines don't quite work right for the MERGE case. - * - * A special mergeSourceTargetList is setup by transformMergeJoinClause(). - * It refers to all the attributes provided by the source relation. This - * is later used by set_plan_refs() to fix the UPDATE/INSERT target lists - * to so that they can correctly fetch the attributes from the source - * relation. - * - * The target relation when used in the underlying join, gets a new RTE - * with rte->inh set to true. We remember this RTE (and later pass on to - * the planner and executor) for two main reasons: - * - * 1. If we ever need to run EvalPlanQual while performing MERGE, we must - * make the modified tuple available to the underlying join query, which is - * using a different RTE from the resultRelation RTE. - * - * 2. rewriteTargetListMerge() requires the RTE of the underlying join in - * order to add junk CTID and TABLEOID attributes. - */ - qry->mergeTarget_relation = transformMergeJoinClause(pstate, (Node *) joinexpr, - &qry->mergeSourceTargetList); - - /* - * The target table referenced in the MERGE is looked up twice; once while - * setting it up as the result relation and again when it's used in the - * underlying the join query. In some rare situations, it may happen that - * these lookups return different results, for example, if a new relation - * with the same name gets created in a schema which is ahead in the - * search_path, in between the two lookups. - * - * It's a very narrow case, but nevertheless we guard against it by simply - * checking if the OIDs returned by the two lookups is the same. If not, we - * just throw an error. - */ - Assert(qry->resultRelation > 0); - Assert(qry->mergeTarget_relation > 0); - - /* Fetch both the RTEs */ - resultRelRTE = rt_fetch(qry->resultRelation, pstate->p_rtable); - mergeRelRTE = rt_fetch(qry->mergeTarget_relation, pstate->p_rtable); - - if (resultRelRTE->relid != mergeRelRTE->relid) - ereport(ERROR, - (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), - errmsg("relation referenced by MERGE statement has changed"))); - - /* - * This query should just provide the source relation columns. Later, in - * preprocess_targetlist(), we shall also add "ctid" attribute of the - * target relation to ensure that the target tuple can be fetched - * correctly. - */ - qry->targetList = qry->mergeSourceTargetList; - - /* qry has no WHERE clause so absent quals are shown as NULL */ - qry->jointree = makeFromExpr(pstate->p_joinlist, NULL); - qry->rtable = pstate->p_rtable; - - /* - * XXX MERGE is unsupported in various cases - */ - if (!(pstate->p_target_relation->rd_rel->relkind == RELKIND_RELATION || - pstate->p_target_relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("MERGE is not supported for this relation type"))); - - if (pstate->p_target_relation->rd_rel->relkind != RELKIND_PARTITIONED_TABLE && - pstate->p_target_relation->rd_rel->relhassubclass) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("MERGE is not supported for relations with inheritance"))); - - if (pstate->p_target_relation->rd_rel->relhasrules) - ereport(ERROR, - (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), - errmsg("MERGE is not supported for relations with rules"))); - - /* - * We now have a good query shape, so now look at the when conditions and - * action targetlists. - * - * Overall, the MERGE Query's targetlist is NIL. - * - * Each individual action has its own targetlist that needs separate - * transformation. These transforms don't do anything to the overall - * targetlist, since that is only used for resjunk columns. - * - * We can reference any column in Target or Source, which is OK because - * both of those already have RTEs. There is nothing like the EXCLUDED - * pseudo-relation for INSERT ON CONFLICT. - */ - mergeActionList = NIL; - foreach(l, stmt->mergeWhenClauses) - { - MergeWhenClause *mergeWhenClause = (MergeWhenClause *) lfirst(l); - MergeAction *action = makeNode(MergeAction); - - action->commandType = mergeWhenClause->commandType; - action->matched = mergeWhenClause->matched; - - /* - * Set namespace for the specific action. This must be done before - * analyzing the WHEN quals and the action targetlisst. - */ - setNamespaceForMergeWhen(pstate, mergeWhenClause); - - /* - * Transform the when condition. - * - * Note that these quals are NOT added to the join quals; instead they - * are evaluated separately during execution to decide which of the - * WHEN MATCHED or WHEN NOT MATCHED actions to execute. - */ - action->qual = transformWhereClause(pstate, mergeWhenClause->condition, - EXPR_KIND_MERGE_WHEN_AND, "WHEN"); - - /* - * Transform target lists for each INSERT and UPDATE action stmt - */ - switch (action->commandType) - { - case CMD_INSERT: - { - List *exprList = NIL; - ListCell *lc; - RangeTblEntry *rte; - ListCell *icols; - ListCell *attnos; - List *icolumns; - List *attrnos; - - pstate->p_is_insert = true; - - icolumns = checkInsertTargets(pstate, - mergeWhenClause->cols, - &attrnos); - Assert(list_length(icolumns) == list_length(attrnos)); - - action->override = mergeWhenClause->override; - - /* - * Handle INSERT much like in transformInsertStmt - */ - if (mergeWhenClause->values == NIL) - { - /* - * We have INSERT ... DEFAULT VALUES. We can handle - * this case by emitting an empty targetlist --- all - * columns will be defaulted when the planner expands - * the targetlist. - */ - exprList = NIL; - } - else - { - /* - * Process INSERT ... VALUES with a single VALUES - * sublist. We treat this case separately for - * efficiency. The sublist is just computed directly - * as the Query's targetlist, with no VALUES RTE. So - * it works just like a SELECT without any FROM. - */ - - /* - * Do basic expression transformation (same as a ROW() - * expr, but allow SetToDefault at top level) - */ - exprList = transformExpressionList(pstate, - mergeWhenClause->values, - EXPR_KIND_VALUES_SINGLE, - true); - - /* Prepare row for assignment to target table */ - exprList = transformInsertRow(pstate, exprList, - mergeWhenClause->cols, - icolumns, attrnos, - false); - } - - /* - * Generate action's target list using the computed list - * of expressions. Also, mark all the target columns as - * needing insert permissions. - */ - rte = pstate->p_target_rangetblentry; - icols = list_head(icolumns); - attnos = list_head(attrnos); - foreach(lc, exprList) - { - Expr *expr = (Expr *) lfirst(lc); - ResTarget *col; - AttrNumber attr_num; - TargetEntry *tle; - - col = lfirst_node(ResTarget, icols); - attr_num = (AttrNumber) lfirst_int(attnos); - - tle = makeTargetEntry(expr, - attr_num, - col->name, - false); - action->targetList = lappend(action->targetList, tle); - - rte->insertedCols = bms_add_member(rte->insertedCols, - attr_num - FirstLowInvalidHeapAttributeNumber); - - icols = lnext(icols); - attnos = lnext(attnos); - } - } - break; - case CMD_UPDATE: - { - pstate->p_is_insert = false; - action->targetList = transformUpdateTargetList(pstate, - mergeWhenClause->targetList); - } - break; - case CMD_DELETE: - break; - - case CMD_NOTHING: - action->targetList = NIL; - break; - default: - elog(ERROR, "unknown action in MERGE WHEN clause"); - } - - mergeActionList = lappend(mergeActionList, action); - } - - qry->mergeActionList = mergeActionList; - - /* XXX maybe later */ - qry->returningList = NULL; - - qry->hasTargetSRFs = false; - qry->hasSubLinks = pstate->p_hasSubLinks; - - assign_query_collations(pstate, qry); - - return qry; -} - -static void -setNamespaceVisibilityForRTE(List *namespace, RangeTblEntry *rte, - bool rel_visible, - bool cols_visible) -{ - ListCell *lc; - - foreach(lc, namespace) - { - ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc); - - if (nsitem->p_rte == rte) - { - nsitem->p_rel_visible = rel_visible; - nsitem->p_cols_visible = cols_visible; - break; - } - } - -} - -/* - * Expand the source relation to include all attributes of this RTE. - * - * This function is very similar to expandRelAttrs except that we don't mark - * columns for SELECT privileges. That will be decided later when we transform - * the action targetlists and the WHEN quals for actual references to the - * source relation. - */ -static List * -expandSourceTL(ParseState *pstate, RangeTblEntry *rte, int rtindex) -{ - List *names, - *vars; - ListCell *name, - *var; - List *te_list = NIL; - - expandRTE(rte, rtindex, 0, -1, false, &names, &vars); - - /* - * Require read access to the table. - */ - rte->requiredPerms |= ACL_SELECT; - - forboth(name, names, var, vars) - { - char *label = strVal(lfirst(name)); - Var *varnode = (Var *) lfirst(var); - TargetEntry *te; - - te = makeTargetEntry((Expr *) varnode, - (AttrNumber) pstate->p_next_resno++, - label, - false); - te_list = lappend(te_list, te); - } - - Assert(name == NULL && var == NULL); /* lists not the same length? */ - - return te_list; -} diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c index 8b912eeea31..bf5df26009a 100644 --- a/src/backend/parser/parse_relation.c +++ b/src/backend/parser/parse_relation.c @@ -728,16 +728,6 @@ scanRTEForColumn(ParseState *pstate, RangeTblEntry *rte, const char *colname, colname), parser_errposition(pstate, location))); - /* In MERGE WHEN AND condition, no system column is allowed except tableOid or OID */ - if (pstate->p_expr_kind == EXPR_KIND_MERGE_WHEN_AND && - attnum < InvalidAttrNumber && - !(attnum == TableOidAttributeNumber || attnum == ObjectIdAttributeNumber)) - ereport(ERROR, - (errcode(ERRCODE_INVALID_COLUMN_REFERENCE), - errmsg("system column \"%s\" reference in WHEN AND condition is invalid", - colname), - parser_errposition(pstate, location))); - if (attnum != InvalidAttrNumber) { /* now check to see if column actually is defined */ |