diff options
Diffstat (limited to 'src/backend/utils/adt/ruleutils.c')
| -rw-r--r-- | src/backend/utils/adt/ruleutils.c | 409 |
1 files changed, 193 insertions, 216 deletions
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 571854d446c..26ebe21c4a2 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -1,9 +1,9 @@ /********************************************************************** - * get_ruledef.c - Function to get a rules definition text - * out of its tuple + * ruleutils.c - Functions to convert stored expressions/querytrees + * back to source text * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.60 2000/09/12 04:15:58 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.61 2000/09/12 21:07:05 tgl Exp $ * * This software is copyrighted by Jan Wieck - Hamburg. * @@ -43,6 +43,7 @@ #include "catalog/pg_index.h" #include "catalog/pg_operator.h" #include "catalog/pg_shadow.h" +#include "commands/view.h" #include "executor/spi.h" #include "lib/stringinfo.h" #include "optimizer/clauses.h" @@ -50,8 +51,8 @@ #include "parser/keywords.h" #include "parser/parse_expr.h" #include "parser/parsetree.h" +#include "rewrite/rewriteManip.h" #include "utils/lsyscache.h" -#include "commands/view.h" /* ---------- @@ -65,12 +66,6 @@ typedef struct bool varprefix; /* TRUE to print prefixes on Vars */ } deparse_context; -typedef struct -{ - Index rt_index; - int levelsup; -} check_if_rte_used_context; - /* ---------- * Global data @@ -108,13 +103,13 @@ static void get_func_expr(Expr *expr, deparse_context *context); static void get_tle_expr(TargetEntry *tle, deparse_context *context); static void get_const_expr(Const *constval, deparse_context *context); static void get_sublink_expr(Node *node, deparse_context *context); +static void get_from_clause(Query *query, deparse_context *context); +static void get_from_clause_item(Node *jtnode, Query *query, + deparse_context *context); static bool tleIsArrayAssign(TargetEntry *tle); static char *quote_identifier(char *ident); static char *get_relation_name(Oid relid); static char *get_attribute_name(Oid relid, int2 attnum); -static bool check_if_rte_used(Node *node, Index rt_index, int levelsup); -static bool check_if_rte_used_walker(Node *node, - check_if_rte_used_context *context); #define only_marker(rte) ((rte)->inh ? "" : "ONLY ") @@ -230,13 +225,13 @@ pg_get_viewdef(PG_FUNCTION_ARGS) Name vname = PG_GETARG_NAME(0); text *ruledef; Datum args[1]; - char nulls[2]; + char nulls[1]; int spirc; HeapTuple ruletup; TupleDesc rulettc; StringInfoData buf; int len; - char *name; + char *name; /* ---------- * We need the view name somewhere deep down @@ -276,7 +271,6 @@ pg_get_viewdef(PG_FUNCTION_ARGS) name = MakeRetrieveViewRuleName(rulename); args[0] = PointerGetDatum(name); nulls[0] = ' '; - nulls[1] = '\0'; spirc = SPI_execp(plan_getview, args, nulls, 1); if (spirc != SPI_OK_SELECT) elog(ERROR, "failed to get pg_rewrite tuple for view %s", rulename); @@ -883,61 +877,9 @@ get_select_query_def(Query *query, deparse_context *context) { StringInfo buf = context->buf; char *sep; - TargetEntry *tle; - RangeTblEntry *rte; - bool *rt_used; - int rt_length; - int rt_numused = 0; - bool rt_constonly = TRUE; - int i; List *l; /* ---------- - * First we need to know which and how many of the - * range table entries in the query are used in the target list - * or queries qualification - * ---------- - */ - rt_length = length(query->rtable); - rt_used = palloc(sizeof(bool) * rt_length); - for (i = 0; i < rt_length; i++) - { - if (check_if_rte_used((Node *) (query->targetList), i + 1, 0) || - check_if_rte_used(query->qual, i + 1, 0) || - check_if_rte_used(query->havingQual, i + 1, 0)) - { - rt_used[i] = TRUE; - rt_numused++; - } - else - rt_used[i] = FALSE; - } - - /* ---------- - * Now check if any of the used rangetable entries is different - * from *NEW* and *OLD*. If so we must provide the FROM clause - * later. - * ---------- - */ - i = 0; - foreach(l, query->rtable) - { - if (!rt_used[i++]) - continue; - - rte = (RangeTblEntry *) lfirst(l); - if (rte->ref == NULL) - continue; - if (strcmp(rte->ref->relname, "*NEW*") == 0) - continue; - if (strcmp(rte->ref->relname, "*OLD*") == 0) - continue; - - rt_constonly = FALSE; - break; - } - - /* ---------- * Build up the query string - first we say SELECT * ---------- */ @@ -947,9 +889,9 @@ get_select_query_def(Query *query, deparse_context *context) sep = " "; foreach(l, query->targetList) { + TargetEntry *tle = (TargetEntry *) lfirst(l); bool tell_as = false; - tle = (TargetEntry *) lfirst(l); appendStringInfo(buf, sep); sep = ", "; @@ -962,6 +904,7 @@ get_select_query_def(Query *query, deparse_context *context) else { Var *var = (Var *) (tle->expr); + RangeTblEntry *rte; char *attname; rte = get_rte_for_var(var, context); @@ -975,60 +918,8 @@ get_select_query_def(Query *query, deparse_context *context) quote_identifier(tle->resdom->resname)); } - /* If we need other tables than *NEW* or *OLD* add the FROM clause */ - if (!rt_constonly && rt_numused > 0) - { - sep = " FROM "; - i = 0; - foreach(l, query->rtable) - { - if (rt_used[i++]) - { - rte = (RangeTblEntry *) lfirst(l); - - if (rte->ref == NULL) - continue; - if (strcmp(rte->ref->relname, "*NEW*") == 0) - continue; - if (strcmp(rte->ref->relname, "*OLD*") == 0) - continue; - - appendStringInfo(buf, sep); - sep = ", "; - appendStringInfo(buf, "%s%s", - only_marker(rte), - quote_identifier(rte->relname)); - - /* - * NOTE: SQL92 says you can't write column aliases unless - * you write a table alias --- so, if there's an alias - * list, make sure we emit a table alias even if it's the - * same as the table's real name. - */ - if ((rte->ref != NULL) - && ((strcmp(rte->relname, rte->ref->relname) != 0) - || (rte->ref->attrs != NIL))) - { - appendStringInfo(buf, " %s", - quote_identifier(rte->ref->relname)); - if (rte->ref->attrs != NIL) - { - List *col; - - appendStringInfo(buf, " ("); - foreach(col, rte->ref->attrs) - { - if (col != rte->ref->attrs) - appendStringInfo(buf, ", "); - appendStringInfo(buf, "%s", - quote_identifier(strVal(lfirst(col)))); - } - appendStringInfoChar(buf, ')'); - } - } - } - } - } + /* Add the FROM clause if needed */ + get_from_clause(query, context); /* Add the WHERE clause if given */ if (query->qual != NULL) @@ -1066,52 +957,32 @@ get_insert_query_def(Query *query, deparse_context *context) { StringInfo buf = context->buf; char *sep; - TargetEntry *tle; - RangeTblEntry *rte; - bool *rt_used; - int rt_length; - int rt_numused = 0; bool rt_constonly = TRUE; + RangeTblEntry *rte; int i; List *l; /* ---------- * We need to know if other tables than *NEW* or *OLD* * are used in the query. If not, it's an INSERT ... VALUES, - * otherwise an INSERT ... SELECT. + * otherwise an INSERT ... SELECT. (Pretty klugy ... fix this + * when we redesign querytrees!) * ---------- */ - rt_length = length(query->rtable); - rt_used = palloc(sizeof(bool) * rt_length); - for (i = 0; i < rt_length; i++) - { - if (check_if_rte_used((Node *) (query->targetList), i + 1, 0) || - check_if_rte_used(query->qual, i + 1, 0) || - check_if_rte_used(query->havingQual, i + 1, 0)) - { - rt_used[i] = TRUE; - rt_numused++; - } - else - rt_used[i] = FALSE; - } - i = 0; foreach(l, query->rtable) { - if (!rt_used[i++]) - continue; - rte = (RangeTblEntry *) lfirst(l); - if (rte->ref == NULL) - continue; - if (strcmp(rte->ref->relname, "*NEW*") == 0) + i++; + if (strcmp(rte->eref->relname, "*NEW*") == 0) continue; - if (strcmp(rte->ref->relname, "*OLD*") == 0) + if (strcmp(rte->eref->relname, "*OLD*") == 0) continue; - - rt_constonly = FALSE; - break; + if (rangeTableEntry_used((Node *) query, i, 0)) + { + rt_constonly = FALSE; + break; + } } /* ---------- @@ -1122,11 +993,11 @@ get_insert_query_def(Query *query, deparse_context *context) appendStringInfo(buf, "INSERT INTO %s", quote_identifier(rte->relname)); - /* Add the target list */ + /* Add the insert-column-names list */ sep = " ("; foreach(l, query->targetList) { - tle = (TargetEntry *) lfirst(l); + TargetEntry *tle = (TargetEntry *) lfirst(l); appendStringInfo(buf, sep); sep = ", "; @@ -1141,7 +1012,7 @@ get_insert_query_def(Query *query, deparse_context *context) sep = ""; foreach(l, query->targetList) { - tle = (TargetEntry *) lfirst(l); + TargetEntry *tle = (TargetEntry *) lfirst(l); appendStringInfo(buf, sep); sep = ", "; @@ -1195,6 +1066,9 @@ get_update_query_def(Query *query, deparse_context *context) get_tle_expr(tle, context); } + /* Add the FROM clause if needed */ + get_from_clause(query, context); + /* Finally add a WHERE clause if given */ if (query->qual != NULL) { @@ -1281,16 +1155,13 @@ get_rule_expr(Node *node, deparse_context *context) if (context->varprefix) { - if (rte->ref == NULL) - appendStringInfo(buf, "%s.", - quote_identifier(rte->relname)); - else if (strcmp(rte->ref->relname, "*NEW*") == 0) + if (strcmp(rte->eref->relname, "*NEW*") == 0) appendStringInfo(buf, "new."); - else if (strcmp(rte->ref->relname, "*OLD*") == 0) + else if (strcmp(rte->eref->relname, "*OLD*") == 0) appendStringInfo(buf, "old."); else appendStringInfo(buf, "%s.", - quote_identifier(rte->ref->relname)); + quote_identifier(rte->eref->relname)); } appendStringInfo(buf, "%s", quote_identifier(get_attribute_name(rte->relid, @@ -1860,6 +1731,165 @@ get_sublink_expr(Node *node, deparse_context *context) appendStringInfoChar(buf, ')'); } + +/* ---------- + * get_from_clause - Parse back a FROM clause + * ---------- + */ +static void +get_from_clause(Query *query, deparse_context *context) +{ + StringInfo buf = context->buf; + char *sep; + List *l; + + /* + * We use the query's jointree as a guide to what to print. However, + * we must ignore auto-added RTEs that are marked not inFromCl. + * Also ignore the rule pseudo-RTEs for NEW and OLD. + */ + sep = " FROM "; + + foreach(l, query->jointree) + { + Node *jtnode = (Node *) lfirst(l); + + if (IsA(jtnode, RangeTblRef)) + { + int varno = ((RangeTblRef *) jtnode)->rtindex; + RangeTblEntry *rte = rt_fetch(varno, query->rtable); + + if (!rte->inFromCl) + continue; + if (strcmp(rte->eref->relname, "*NEW*") == 0) + continue; + if (strcmp(rte->eref->relname, "*OLD*") == 0) + continue; + } + + appendStringInfo(buf, sep); + get_from_clause_item(jtnode, query, context); + sep = ", "; + } +} + +static void +get_from_clause_item(Node *jtnode, Query *query, deparse_context *context) +{ + StringInfo buf = context->buf; + + if (IsA(jtnode, RangeTblRef)) + { + int varno = ((RangeTblRef *) jtnode)->rtindex; + RangeTblEntry *rte = rt_fetch(varno, query->rtable); + + appendStringInfo(buf, "%s%s", + only_marker(rte), + quote_identifier(rte->relname)); + if (rte->alias != NULL) + { + appendStringInfo(buf, " %s", + quote_identifier(rte->alias->relname)); + if (rte->alias->attrs != NIL) + { + List *col; + + appendStringInfo(buf, " ("); + foreach(col, rte->alias->attrs) + { + if (col != rte->alias->attrs) + appendStringInfo(buf, ", "); + appendStringInfo(buf, "%s", + quote_identifier(strVal(lfirst(col)))); + } + appendStringInfoChar(buf, ')'); + } + } + } + else if (IsA(jtnode, JoinExpr)) + { + JoinExpr *j = (JoinExpr *) jtnode; + + appendStringInfoChar(buf, '('); + get_from_clause_item(j->larg, query, context); + if (j->isNatural) + appendStringInfo(buf, " NATURAL"); + switch (j->jointype) + { + case JOIN_INNER: + if (j->quals) + appendStringInfo(buf, " JOIN "); + else + appendStringInfo(buf, " CROSS JOIN "); + break; + case JOIN_LEFT: + appendStringInfo(buf, " LEFT JOIN "); + break; + case JOIN_FULL: + appendStringInfo(buf, " FULL JOIN "); + break; + case JOIN_RIGHT: + appendStringInfo(buf, " RIGHT JOIN "); + break; + case JOIN_UNION: + appendStringInfo(buf, " UNION JOIN "); + break; + default: + elog(ERROR, "get_from_clause_item: unknown join type %d", + (int) j->jointype); + } + get_from_clause_item(j->rarg, query, context); + if (! j->isNatural) + { + if (j->using) + { + List *col; + + appendStringInfo(buf, " USING ("); + foreach(col, j->using) + { + if (col != j->using) + appendStringInfo(buf, ", "); + appendStringInfo(buf, "%s", + quote_identifier(strVal(lfirst(col)))); + } + appendStringInfoChar(buf, ')'); + } + else if (j->quals) + { + appendStringInfo(buf, " ON ("); + get_rule_expr(j->quals, context); + appendStringInfoChar(buf, ')'); + } + } + appendStringInfoChar(buf, ')'); + /* Yes, it's correct to put alias after the right paren ... */ + if (j->alias != NULL) + { + appendStringInfo(buf, " %s", + quote_identifier(j->alias->relname)); + if (j->alias->attrs != NIL) + { + List *col; + + appendStringInfo(buf, " ("); + foreach(col, j->alias->attrs) + { + if (col != j->alias->attrs) + appendStringInfo(buf, ", "); + appendStringInfo(buf, "%s", + quote_identifier(strVal(lfirst(col)))); + } + appendStringInfoChar(buf, ')'); + } + } + } + else + elog(ERROR, "get_from_clause_item: unexpected node type %d", + nodeTag(jtnode)); +} + + /* ---------- * tleIsArrayAssign - check for array assignment * ---------- @@ -1990,56 +2020,3 @@ get_attribute_name(Oid relid, int2 attnum) attStruct = (Form_pg_attribute) GETSTRUCT(atttup); return pstrdup(NameStr(attStruct->attname)); } - - -/* ---------- - * check_if_rte_used - * Check a targetlist or qual to see if a given rangetable entry - * is used in it - * ---------- - */ -static bool -check_if_rte_used(Node *node, Index rt_index, int levelsup) -{ - check_if_rte_used_context context; - - context.rt_index = rt_index; - context.levelsup = levelsup; - return check_if_rte_used_walker(node, &context); -} - -static bool -check_if_rte_used_walker(Node *node, - check_if_rte_used_context *context) -{ - if (node == NULL) - return false; - if (IsA(node, Var)) - { - Var *var = (Var *) node; - - return var->varno == context->rt_index && - var->varlevelsup == context->levelsup; - } - if (IsA(node, SubLink)) - { - SubLink *sublink = (SubLink *) node; - Query *query = (Query *) sublink->subselect; - - /* Recurse into subquery; expression_tree_walker will not */ - if (check_if_rte_used((Node *) (query->targetList), - context->rt_index, context->levelsup + 1) || - check_if_rte_used(query->qual, - context->rt_index, context->levelsup + 1) || - check_if_rte_used(query->havingQual, - context->rt_index, context->levelsup + 1)) - return true; - - /* - * fall through to let expression_tree_walker examine lefthand - * args - */ - } - return expression_tree_walker(node, check_if_rte_used_walker, - (void *) context); -} |