diff options
Diffstat (limited to 'src/backend/parser/analyze.c')
| -rw-r--r-- | src/backend/parser/analyze.c | 90 |
1 files changed, 84 insertions, 6 deletions
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c index c441be220e2..8a19697a71c 100644 --- a/src/backend/parser/analyze.c +++ b/src/backend/parser/analyze.c @@ -17,7 +17,7 @@ * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.390 2009/08/27 20:08:02 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.391 2009/09/09 03:32:52 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -50,7 +50,9 @@ static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt); static Query *transformValuesClause(ParseState *pstate, SelectStmt *stmt); static Query *transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt); static Node *transformSetOperationTree(ParseState *pstate, SelectStmt *stmt, - List **colInfo); + bool isTopLevel, List **colInfo); +static void determineRecursiveColTypes(ParseState *pstate, + Node *larg, List *lcolinfo); static void applyColumnNames(List *dst, List *src); static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt); static List *transformReturningList(ParseState *pstate, List *returningList); @@ -135,11 +137,14 @@ parse_analyze_varparams(Node *parseTree, const char *sourceText, * Entry point for recursively analyzing a sub-statement. */ Query * -parse_sub_analyze(Node *parseTree, ParseState *parentParseState) +parse_sub_analyze(Node *parseTree, ParseState *parentParseState, + CommonTableExpr *parentCTE) { ParseState *pstate = make_parsestate(parentParseState); Query *query; + pstate->p_parent_cte = parentCTE; + query = transformStmt(pstate, parseTree); free_parsestate(pstate); @@ -1199,6 +1204,7 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt) * Recursively transform the components of the tree. */ sostmt = (SetOperationStmt *) transformSetOperationTree(pstate, stmt, + true, &socolinfo); Assert(sostmt && IsA(sostmt, SetOperationStmt)); qry->setOperations = (Node *) sostmt; @@ -1359,7 +1365,7 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt) */ static Node * transformSetOperationTree(ParseState *pstate, SelectStmt *stmt, - List **colInfo) + bool isTopLevel, List **colInfo) { bool isLeaf; @@ -1418,7 +1424,7 @@ transformSetOperationTree(ParseState *pstate, SelectStmt *stmt, * of this sub-query, because they are not in the toplevel pstate's * namespace list. */ - selectQuery = parse_sub_analyze((Node *) stmt, pstate); + selectQuery = parse_sub_analyze((Node *) stmt, pstate, NULL); /* * Check for bogus references to Vars on the current query level (but @@ -1485,11 +1491,28 @@ transformSetOperationTree(ParseState *pstate, SelectStmt *stmt, op->all = stmt->all; /* - * Recursively transform the child nodes. + * Recursively transform the left child node. */ op->larg = transformSetOperationTree(pstate, stmt->larg, + false, &lcolinfo); + + /* + * If we are processing a recursive union query, now is the time + * to examine the non-recursive term's output columns and mark the + * containing CTE as having those result columns. We should do this + * only at the topmost setop of the CTE, of course. + */ + if (isTopLevel && + pstate->p_parent_cte && + pstate->p_parent_cte->cterecursive) + determineRecursiveColTypes(pstate, op->larg, lcolinfo); + + /* + * Recursively transform the right child node. + */ op->rarg = transformSetOperationTree(pstate, stmt->rarg, + false, &rcolinfo); /* @@ -1585,6 +1608,61 @@ transformSetOperationTree(ParseState *pstate, SelectStmt *stmt, } /* + * Process the outputs of the non-recursive term of a recursive union + * to set up the parent CTE's columns + */ +static void +determineRecursiveColTypes(ParseState *pstate, Node *larg, List *lcolinfo) +{ + Node *node; + int leftmostRTI; + Query *leftmostQuery; + List *targetList; + ListCell *left_tlist; + ListCell *lci; + int next_resno; + + /* + * Find leftmost leaf SELECT + */ + node = larg; + while (node && IsA(node, SetOperationStmt)) + node = ((SetOperationStmt *) node)->larg; + Assert(node && IsA(node, RangeTblRef)); + leftmostRTI = ((RangeTblRef *) node)->rtindex; + leftmostQuery = rt_fetch(leftmostRTI, pstate->p_rtable)->subquery; + Assert(leftmostQuery != NULL); + + /* + * Generate dummy targetlist using column names of leftmost select + * and dummy result expressions of the non-recursive term. + */ + targetList = NIL; + left_tlist = list_head(leftmostQuery->targetList); + next_resno = 1; + + foreach(lci, lcolinfo) + { + Expr *lcolexpr = (Expr *) lfirst(lci); + TargetEntry *lefttle = (TargetEntry *) lfirst(left_tlist); + char *colName; + TargetEntry *tle; + + Assert(!lefttle->resjunk); + colName = pstrdup(lefttle->resname); + tle = makeTargetEntry(lcolexpr, + next_resno++, + colName, + false); + targetList = lappend(targetList, tle); + left_tlist = lnext(left_tlist); + } + + /* Now build CTE's output column info using dummy targetlist */ + analyzeCTETargetList(pstate, pstate->p_parent_cte, targetList); +} + +/* * Attach column names from a ColumnDef list to a TargetEntry list * (for CREATE TABLE AS) */ |