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Diffstat (limited to 'src/backend/utils/adt/ruleutils.c')
-rw-r--r--src/backend/utils/adt/ruleutils.c137
1 files changed, 79 insertions, 58 deletions
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 9f21a609f3d..47f61865fc3 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -3,7 +3,7 @@
* back to source text
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.122 2002/09/18 21:35:23 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.123 2002/09/19 22:48:33 tgl Exp $
*
* This software is copyrighted by Jan Wieck - Hamburg.
*
@@ -147,9 +147,11 @@ static void get_names_for_var(Var *var, deparse_context *context,
char **schemaname, char **refname, char **attname);
static RangeTblEntry *find_rte_by_refname(const char *refname,
deparse_context *context);
-static void get_rule_expr(Node *node, deparse_context *context);
+static void get_rule_expr(Node *node, deparse_context *context,
+ bool showimplicit);
static void get_oper_expr(Expr *expr, deparse_context *context);
-static void get_func_expr(Expr *expr, deparse_context *context);
+static void get_func_expr(Expr *expr, deparse_context *context,
+ bool showimplicit);
static void get_agg_expr(Aggref *aggref, deparse_context *context);
static Node *strip_type_coercion(Node *expr, Oid resultType);
static void get_const_expr(Const *constval, deparse_context *context);
@@ -515,7 +517,7 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
node = (Node *) make_ands_explicit((List *) node);
/* Deparse */
context = deparse_context_for(get_rel_name(indrelid), indrelid);
- str = deparse_expression(node, context, false);
+ str = deparse_expression(node, context, false, false);
appendStringInfo(&buf, " WHERE %s", str);
}
@@ -792,7 +794,7 @@ pg_get_expr(PG_FUNCTION_ARGS)
/* Deparse */
context = deparse_context_for(relname, relid);
- str = deparse_expression(node, context, false);
+ str = deparse_expression(node, context, false, false);
/* Pass the result back as TEXT */
result = DatumGetTextP(DirectFunctionCall1(textin,
@@ -850,11 +852,14 @@ pg_get_userbyid(PG_FUNCTION_ARGS)
*
* forceprefix is TRUE to force all Vars to be prefixed with their table names.
*
+ * showimplicit is TRUE to force all implicit casts to be shown explicitly.
+ *
* The result is a palloc'd string.
* ----------
*/
char *
-deparse_expression(Node *expr, List *dpcontext, bool forceprefix)
+deparse_expression(Node *expr, List *dpcontext,
+ bool forceprefix, bool showimplicit)
{
StringInfoData buf;
deparse_context context;
@@ -864,7 +869,7 @@ deparse_expression(Node *expr, List *dpcontext, bool forceprefix)
context.namespaces = dpcontext;
context.varprefix = forceprefix;
- get_rule_expr(expr, &context);
+ get_rule_expr(expr, &context, showimplicit);
return buf.data;
}
@@ -1139,7 +1144,7 @@ make_ruledef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc)
dpns.outer_varno = dpns.inner_varno = 0;
dpns.outer_rte = dpns.inner_rte = NULL;
- get_rule_expr(qual, &context);
+ get_rule_expr(qual, &context, false);
}
appendStringInfo(buf, " DO ");
@@ -1364,7 +1369,7 @@ get_select_query_def(Query *query, deparse_context *context,
if (query->limitOffset != NULL)
{
appendStringInfo(buf, " OFFSET ");
- get_rule_expr(query->limitOffset, context);
+ get_rule_expr(query->limitOffset, context, false);
}
if (query->limitCount != NULL)
{
@@ -1373,7 +1378,7 @@ get_select_query_def(Query *query, deparse_context *context,
((Const *) query->limitCount)->constisnull)
appendStringInfo(buf, "ALL");
else
- get_rule_expr(query->limitCount, context);
+ get_rule_expr(query->limitCount, context, false);
}
}
@@ -1429,7 +1434,7 @@ get_basic_select_query(Query *query, deparse_context *context,
sep = ", ";
colno++;
- get_rule_expr(tle->expr, context);
+ get_rule_expr(tle->expr, context, true);
/*
* Figure out what the result column should be called. In the
@@ -1469,7 +1474,7 @@ get_basic_select_query(Query *query, deparse_context *context,
if (query->jointree->quals != NULL)
{
appendStringInfo(buf, " WHERE ");
- get_rule_expr(query->jointree->quals, context);
+ get_rule_expr(query->jointree->quals, context, false);
}
/* Add the GROUP BY clause if given */
@@ -1492,7 +1497,7 @@ get_basic_select_query(Query *query, deparse_context *context,
if (query->havingQual != NULL)
{
appendStringInfo(buf, " HAVING ");
- get_rule_expr(query->havingQual, context);
+ get_rule_expr(query->havingQual, context, false);
}
}
@@ -1573,7 +1578,7 @@ get_rule_sortgroupclause(SortClause *srt, List *tlist, bool force_colno,
appendStringInfo(buf, "%d", tle->resdom->resno);
}
else
- get_rule_expr(expr, context);
+ get_rule_expr(expr, context, true);
return expr;
}
@@ -1642,7 +1647,7 @@ get_insert_query_def(Query *query, deparse_context *context)
appendStringInfo(buf, sep);
sep = ", ";
- get_rule_expr(tle->expr, context);
+ get_rule_expr(tle->expr, context, false);
}
appendStringInfoChar(buf, ')');
}
@@ -1692,7 +1697,7 @@ get_update_query_def(Query *query, deparse_context *context)
if (!tleIsArrayAssign(tle))
appendStringInfo(buf, "%s = ",
quote_identifier(tle->resdom->resname));
- get_rule_expr(tle->expr, context);
+ get_rule_expr(tle->expr, context, false);
}
/* Add the FROM clause if needed */
@@ -1702,7 +1707,7 @@ get_update_query_def(Query *query, deparse_context *context)
if (query->jointree->quals != NULL)
{
appendStringInfo(buf, " WHERE ");
- get_rule_expr(query->jointree->quals, context);
+ get_rule_expr(query->jointree->quals, context, false);
}
}
@@ -1730,7 +1735,7 @@ get_delete_query_def(Query *query, deparse_context *context)
if (query->jointree->quals != NULL)
{
appendStringInfo(buf, " WHERE ");
- get_rule_expr(query->jointree->quals, context);
+ get_rule_expr(query->jointree->quals, context, false);
}
}
@@ -1890,10 +1895,20 @@ find_rte_by_refname(const char *refname, deparse_context *context)
/* ----------
* get_rule_expr - Parse back an expression
+ *
+ * Note: showimplicit determines whether we display any implicit cast that
+ * is present at the top of the expression tree. It is a passed argument,
+ * not a field of the context struct, because we change the value as we
+ * recurse down into the expression. In general we suppress implicit casts
+ * when the result type is known with certainty (eg, the arguments of an
+ * OR must be boolean). We display implicit casts for arguments of functions
+ * and operators, since this is needed to be certain that the same function
+ * or operator will be chosen when the expression is re-parsed.
* ----------
*/
static void
-get_rule_expr(Node *node, deparse_context *context)
+get_rule_expr(Node *node, deparse_context *context,
+ bool showimplicit)
{
StringInfo buf = context->buf;
@@ -1966,42 +1981,44 @@ get_rule_expr(Node *node, deparse_context *context)
Node *arg1 = (Node *) lfirst(args);
Node *arg2 = (Node *) lsecond(args);
- get_rule_expr(arg1, context);
+ get_rule_expr(arg1, context, true);
appendStringInfo(buf, " IS DISTINCT FROM ");
- get_rule_expr(arg2, context);
+ get_rule_expr(arg2, context, true);
}
appendStringInfoChar(buf, ')');
break;
case FUNC_EXPR:
- get_func_expr(expr, context);
+ get_func_expr(expr, context, showimplicit);
break;
case OR_EXPR:
appendStringInfoChar(buf, '(');
- get_rule_expr((Node *) lfirst(args), context);
+ get_rule_expr((Node *) lfirst(args), context, false);
while ((args = lnext(args)) != NIL)
{
appendStringInfo(buf, " OR ");
- get_rule_expr((Node *) lfirst(args), context);
+ get_rule_expr((Node *) lfirst(args), context,
+ false);
}
appendStringInfoChar(buf, ')');
break;
case AND_EXPR:
appendStringInfoChar(buf, '(');
- get_rule_expr((Node *) lfirst(args), context);
+ get_rule_expr((Node *) lfirst(args), context, false);
while ((args = lnext(args)) != NIL)
{
appendStringInfo(buf, " AND ");
- get_rule_expr((Node *) lfirst(args), context);
+ get_rule_expr((Node *) lfirst(args), context,
+ false);
}
appendStringInfoChar(buf, ')');
break;
case NOT_EXPR:
appendStringInfo(buf, "(NOT ");
- get_rule_expr((Node *) lfirst(args), context);
+ get_rule_expr((Node *) lfirst(args), context, false);
appendStringInfoChar(buf, ')');
break;
@@ -2042,7 +2059,7 @@ get_rule_expr(Node *node, deparse_context *context)
*/
if (aref->refassgnexpr)
context->varprefix = false;
- get_rule_expr(aref->refexpr, context);
+ get_rule_expr(aref->refexpr, context, showimplicit);
context->varprefix = savevarprefix;
lowlist = aref->reflowerindexpr;
foreach(uplist, aref->refupperindexpr)
@@ -2050,17 +2067,18 @@ get_rule_expr(Node *node, deparse_context *context)
appendStringInfo(buf, "[");
if (lowlist)
{
- get_rule_expr((Node *) lfirst(lowlist), context);
+ get_rule_expr((Node *) lfirst(lowlist), context,
+ false);
appendStringInfo(buf, ":");
lowlist = lnext(lowlist);
}
- get_rule_expr((Node *) lfirst(uplist), context);
+ get_rule_expr((Node *) lfirst(uplist), context, false);
appendStringInfo(buf, "]");
}
if (aref->refassgnexpr)
{
appendStringInfo(buf, " = ");
- get_rule_expr(aref->refassgnexpr, context);
+ get_rule_expr(aref->refassgnexpr, context, showimplicit);
}
}
break;
@@ -2096,7 +2114,7 @@ get_rule_expr(Node *node, deparse_context *context)
* are *not* simple. So, always use parenthesized syntax.
*/
appendStringInfoChar(buf, '(');
- get_rule_expr(fselect->arg, context);
+ get_rule_expr(fselect->arg, context, true);
appendStringInfo(buf, ").%s", quote_identifier(fieldname));
}
break;
@@ -2106,10 +2124,11 @@ get_rule_expr(Node *node, deparse_context *context)
RelabelType *relabel = (RelabelType *) node;
Node *arg = relabel->arg;
- if (relabel->relabelformat == COERCE_IMPLICIT_CAST)
+ if (relabel->relabelformat == COERCE_IMPLICIT_CAST &&
+ !showimplicit)
{
- /* don't show an implicit cast */
- get_rule_expr(arg, context);
+ /* don't show the implicit cast */
+ get_rule_expr(arg, context, showimplicit);
}
else
{
@@ -2122,7 +2141,7 @@ get_rule_expr(Node *node, deparse_context *context)
arg = strip_type_coercion(arg, relabel->resulttype);
appendStringInfoChar(buf, '(');
- get_rule_expr(arg, context);
+ get_rule_expr(arg, context, showimplicit);
appendStringInfo(buf, ")::%s",
format_type_with_typemod(relabel->resulttype,
relabel->resulttypmod));
@@ -2141,12 +2160,12 @@ get_rule_expr(Node *node, deparse_context *context)
CaseWhen *when = (CaseWhen *) lfirst(temp);
appendStringInfo(buf, " WHEN ");
- get_rule_expr(when->expr, context);
+ get_rule_expr(when->expr, context, false);
appendStringInfo(buf, " THEN ");
- get_rule_expr(when->result, context);
+ get_rule_expr(when->result, context, true);
}
appendStringInfo(buf, " ELSE ");
- get_rule_expr(caseexpr->defresult, context);
+ get_rule_expr(caseexpr->defresult, context, true);
appendStringInfo(buf, " END");
}
break;
@@ -2156,7 +2175,7 @@ get_rule_expr(Node *node, deparse_context *context)
NullTest *ntest = (NullTest *) node;
appendStringInfo(buf, "(");
- get_rule_expr(ntest->arg, context);
+ get_rule_expr(ntest->arg, context, true);
switch (ntest->nulltesttype)
{
case IS_NULL:
@@ -2177,7 +2196,7 @@ get_rule_expr(Node *node, deparse_context *context)
BooleanTest *btest = (BooleanTest *) node;
appendStringInfo(buf, "(");
- get_rule_expr(btest->arg, context);
+ get_rule_expr(btest->arg, context, false);
switch (btest->booltesttype)
{
case IS_TRUE:
@@ -2213,7 +2232,7 @@ get_rule_expr(Node *node, deparse_context *context)
* We assume that the operations of the constraint node
* need not be explicitly represented in the output.
*/
- get_rule_expr(ctest->arg, context);
+ get_rule_expr(ctest->arg, context, showimplicit);
}
break;
@@ -2267,12 +2286,12 @@ get_oper_expr(Expr *expr, deparse_context *context)
Node *arg1 = (Node *) lfirst(args);
Node *arg2 = (Node *) lsecond(args);
- get_rule_expr(arg1, context);
+ get_rule_expr(arg1, context, true);
appendStringInfo(buf, " %s ",
generate_operator_name(opno,
exprType(arg1),
exprType(arg2)));
- get_rule_expr(arg2, context);
+ get_rule_expr(arg2, context, true);
}
else
{
@@ -2294,10 +2313,10 @@ get_oper_expr(Expr *expr, deparse_context *context)
generate_operator_name(opno,
InvalidOid,
exprType(arg)));
- get_rule_expr(arg, context);
+ get_rule_expr(arg, context, true);
break;
case 'r':
- get_rule_expr(arg, context);
+ get_rule_expr(arg, context, true);
appendStringInfo(buf, " %s",
generate_operator_name(opno,
exprType(arg),
@@ -2315,7 +2334,8 @@ get_oper_expr(Expr *expr, deparse_context *context)
* get_func_expr - Parse back a Func node
*/
static void
-get_func_expr(Expr *expr, deparse_context *context)
+get_func_expr(Expr *expr, deparse_context *context,
+ bool showimplicit)
{
StringInfo buf = context->buf;
Func *func = (Func *) (expr->oper);
@@ -2327,19 +2347,20 @@ get_func_expr(Expr *expr, deparse_context *context)
/*
* If the function call came from an implicit coercion, then just show
- * the first argument.
+ * the first argument --- unless caller wants to see implicit coercions.
*/
- if (func->funcformat == COERCE_IMPLICIT_CAST)
+ if (func->funcformat == COERCE_IMPLICIT_CAST && !showimplicit)
{
- get_rule_expr((Node *) lfirst(expr->args), context);
+ get_rule_expr((Node *) lfirst(expr->args), context, showimplicit);
return;
}
/*
- * If the function call came from an explicit cast, then show
+ * If the function call came from a cast, then show
* the first argument plus an explicit cast operation.
*/
- if (func->funcformat == COERCE_EXPLICIT_CAST)
+ if (func->funcformat == COERCE_EXPLICIT_CAST ||
+ func->funcformat == COERCE_IMPLICIT_CAST)
{
Node *arg = lfirst(expr->args);
Oid rettype = expr->typeOid;
@@ -2357,7 +2378,7 @@ get_func_expr(Expr *expr, deparse_context *context)
arg = strip_type_coercion(arg, rettype);
appendStringInfoChar(buf, '(');
- get_rule_expr(arg, context);
+ get_rule_expr(arg, context, showimplicit);
appendStringInfo(buf, ")::%s",
format_type_with_typemod(rettype, coercedTypmod));
@@ -2384,7 +2405,7 @@ get_func_expr(Expr *expr, deparse_context *context)
{
appendStringInfo(buf, sep);
sep = ", ";
- get_rule_expr((Node *) lfirst(l), context);
+ get_rule_expr((Node *) lfirst(l), context, true);
}
appendStringInfoChar(buf, ')');
}
@@ -2404,7 +2425,7 @@ get_agg_expr(Aggref *aggref, deparse_context *context)
if (aggref->aggstar)
appendStringInfo(buf, "*");
else
- get_rule_expr(aggref->target, context);
+ get_rule_expr(aggref->target, context, true);
appendStringInfoChar(buf, ')');
}
@@ -2618,7 +2639,7 @@ get_sublink_expr(Node *node, deparse_context *context)
{
appendStringInfo(buf, sep);
sep = ", ";
- get_rule_expr((Node *) lfirst(l), context);
+ get_rule_expr((Node *) lfirst(l), context, true);
}
if (need_paren)
@@ -2750,7 +2771,7 @@ get_from_clause_item(Node *jtnode, Query *query, deparse_context *context)
break;
case RTE_FUNCTION:
/* Function RTE */
- get_rule_expr(rte->funcexpr, context);
+ get_rule_expr(rte->funcexpr, context, true);
/* might need to emit column list for RECORD function */
coldeflist = rte->coldeflist;
break;
@@ -2850,7 +2871,7 @@ get_from_clause_item(Node *jtnode, Query *query, deparse_context *context)
else if (j->quals)
{
appendStringInfo(buf, " ON (");
- get_rule_expr(j->quals, context);
+ get_rule_expr(j->quals, context, false);
appendStringInfoChar(buf, ')');
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-17 13:40:33 +0000