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Implement CASE expression.
This commit is contained in:
Thomas G. Lockhart
@ -7,7 +7,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/parser/parse_target.c,v 1.30 1998/10/08 18:29:47 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/parser/parse_target.c,v 1.31 1998/12/04 15:34:30 thomas Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -39,6 +39,9 @@ static Node *SizeTargetExpr(ParseState *pstate,
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Oid attrtype,
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int32 attrtypmod);
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static TargetEntry *
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MakeTargetEntryCase(ParseState *pstate,
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ResTarget *res);
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/* MakeTargetEntryIdent()
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* Transforms an Ident Node to a Target Entry
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@ -53,11 +56,7 @@ static Node *SizeTargetExpr(ParseState *pstate,
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*/
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TargetEntry *
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MakeTargetEntryIdent(ParseState *pstate,
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#if FALSE
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Ident *ident,
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#else
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Node *node,
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#endif
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char **resname,
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char *refname,
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char *colname,
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@ -77,7 +76,7 @@ MakeTargetEntryIdent(ParseState *pstate,
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pstate->p_insert_columns = lnext(pstate->p_insert_columns);
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}
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else
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elog(ERROR, "insert: more expressions than target columns");
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elog(ERROR, "INSERT has more expressions than target columns");
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}
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if (pstate->p_is_insert || pstate->p_is_update)
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@ -105,7 +104,7 @@ MakeTargetEntryIdent(ParseState *pstate,
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{
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rte = colnameRangeTableEntry(pstate, colname);
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if (rte == (RangeTblEntry *) NULL)
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elog(ERROR, "attribute %s not found", colname);
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elog(ERROR, "Attribute %s not found", colname);
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refname = rte->refname;
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}
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@ -129,14 +128,9 @@ MakeTargetEntryIdent(ParseState *pstate,
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}
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else
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{
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#if TRUE
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elog(ERROR, "Unable to convert %s to %s for column %s",
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typeidTypeName(attrtype_id), typeidTypeName(attrtype_target),
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target_colname);
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#else
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elog(ERROR, "Type or size of %s(%d) does not match target column %s(%d)",
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colname, attrtypmod, target_colname, attrtypmod_target);
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#endif
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}
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}
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}
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@ -152,11 +146,7 @@ MakeTargetEntryIdent(ParseState *pstate,
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name = ((*resname != NULL) ? *resname : colname);
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#if FALSE
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expr = transformIdent(pstate, (Node *) ident, EXPR_COLUMN_FIRST);
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#else
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expr = transformExpr(pstate, node, EXPR_COLUMN_FIRST);
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#endif
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attrtype_target = exprType(expr);
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if (nodeTag(expr) == T_Var)
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@ -187,7 +177,7 @@ MakeTargetEntryIdent(ParseState *pstate,
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* - thomas 1998-05-08
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*
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* Added resjunk flag and made extern so that it can be use by GROUP/
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* ORDER BY a function or expersion not in the target_list
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* ORDER BY a function or expression not in the target_list
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* - daveh@insightdist.com 1998-07-31
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*/
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TargetEntry *
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@ -207,7 +197,7 @@ MakeTargetEntryExpr(ParseState *pstate,
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Resdom *resnode;
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if (expr == NULL)
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elog(ERROR, "MakeTargetEntryExpr: invalid use of NULL expression");
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elog(ERROR, "Invalid use of NULL expression (internal error)");
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type_id = exprType(expr);
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if (nodeTag(expr) == T_Var)
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@ -251,9 +241,9 @@ MakeTargetEntryExpr(ParseState *pstate,
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expr = CoerceTargetExpr(pstate, expr, type_id, typelem);
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if (!HeapTupleIsValid(expr))
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elog(ERROR, "parser: attribute '%s' is of type '%s'"
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elog(ERROR, "Attribute '%s' is of type '%s'"
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" but expression is of type '%s'"
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"\n\tYou will need to rewrite or cast the expression",
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"\n\tYou will need to rewrite or cast the expression",
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colname,
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typeidTypeName(attrtype),
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typeidTypeName(type_id));
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@ -323,6 +313,45 @@ MakeTargetEntryExpr(ParseState *pstate,
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return makeTargetEntry(resnode, expr);
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} /* MakeTargetEntryExpr() */
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/*
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* MakeTargetEntryCase()
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* Make a TargetEntry from a case node.
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*/
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static TargetEntry *
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MakeTargetEntryCase(ParseState *pstate,
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ResTarget *res)
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{
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TargetEntry *tent;
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CaseExpr *expr;
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Resdom *resnode;
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int resdomno;
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Oid type_id;
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int32 type_mod;
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expr = (CaseExpr *)transformExpr(pstate, (Node *)res->val, EXPR_COLUMN_FIRST);
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type_id = expr->casetype;
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type_mod = -1;
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handleTargetColname(pstate, &res->name, NULL, NULL);
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if (res->name == NULL)
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res->name = FigureColname((Node *)expr, res->val);
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resdomno = pstate->p_last_resno++;
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resnode = makeResdom((AttrNumber) resdomno,
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(Oid) type_id,
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type_mod,
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res->name,
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(Index) 0,
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(Oid) 0,
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0);
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tent = makeNode(TargetEntry);
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tent->resdom = resnode;
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tent->expr = (Node *)expr;
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return tent;
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} /* MakeTargetEntryCase() */
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/*
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* MakeTargetEntryComplex()
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* Make a TargetEntry from a complex node.
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@ -351,7 +380,7 @@ MakeTargetEntryComplex(ParseState *pstate,
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Value *constval;
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if (exprType(expr) != UNKNOWNOID || !IsA(expr, Const))
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elog(ERROR, "yyparse: string constant expected");
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elog(ERROR, "String constant expected (internal error)");
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val = (char *) textout((struct varlena *)
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((Const *) expr)->constvalue);
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@ -376,7 +405,7 @@ MakeTargetEntryComplex(ParseState *pstate,
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else
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lindx[i] = 1;
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if (lindx[i] > uindx[i])
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elog(ERROR, "yyparse: lower index cannot be greater than upper index");
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elog(ERROR, "Lower index cannot be greater than upper index");
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sprintf(str, "[%d:%d]", lindx[i], uindx[i]);
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str += strlen(str);
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@ -388,7 +417,7 @@ MakeTargetEntryComplex(ParseState *pstate,
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resdomno = attnameAttNum(rd, res->name);
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ndims = attnumAttNelems(rd, resdomno);
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if (i != ndims)
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elog(ERROR, "yyparse: array dimensions do not match");
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elog(ERROR, "Array dimensions do not match");
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constval = makeNode(Value);
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constval->type = T_String;
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@ -400,9 +429,9 @@ MakeTargetEntryComplex(ParseState *pstate,
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}
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else
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{
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char *colname = res->name;
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/* this is not an array assignment */
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char *colname = res->name;
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if (colname == NULL)
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{
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@ -540,6 +569,11 @@ transformTargetList(ParseState *pstate, List *targetlist)
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tent = MakeTargetEntryComplex(pstate, res);
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break;
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}
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case T_CaseExpr:
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{
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tent = MakeTargetEntryCase(pstate, res);
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break;
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}
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case T_Attr:
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{
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bool expand_star = false;
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@ -604,7 +638,7 @@ transformTargetList(ParseState *pstate, List *targetlist)
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}
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default:
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/* internal error */
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elog(ERROR, "internal error: do not know how to transform targetlist");
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elog(ERROR, "Unable to transform targetlist (internal error)");
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break;
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}
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@ -788,7 +822,7 @@ ExpandAllTables(ParseState *pstate)
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/* this should not happen */
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if (rtable == NULL)
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elog(ERROR, "cannot expand: null p_rtable");
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elog(ERROR, "Cannot expand tables; null p_rtable (internal error)");
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/*
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* go through the range table and make a list of range table entries
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@ -838,7 +872,7 @@ FigureColname(Node *expr, Node *resval)
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{
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switch (nodeTag(expr))
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{
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case T_Aggreg:
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case T_Aggreg:
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return (char *) ((Aggreg *) expr)->aggname;
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case T_Expr:
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if (((Expr *) expr)->opType == FUNC_EXPR)
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