* rewriteDefine.c
* routines for defining a rewrite rule
*
- * Copyright (c) 1994, Regents of the University of California
+ * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteDefine.c,v 1.40 1999/11/18 13:56:27 wieck Exp $
+ * $PostgreSQL: pgsql/src/backend/rewrite/rewriteDefine.c,v 1.130 2008/10/04 21:56:54 tgl Exp $
*
*-------------------------------------------------------------------------
*/
-
#include "postgres.h"
#include "access/heapam.h"
-#include "utils/builtins.h"
+#include "catalog/dependency.h"
+#include "catalog/indexing.h"
+#include "catalog/namespace.h"
#include "catalog/pg_rewrite.h"
-#include "lib/stringinfo.h"
-#include "parser/parse_relation.h"
+#include "miscadmin.h"
+#include "nodes/nodeFuncs.h"
+#include "parser/parse_utilcmd.h"
#include "rewrite/rewriteDefine.h"
+#include "rewrite/rewriteManip.h"
#include "rewrite/rewriteSupport.h"
-#include "tcop/tcopprot.h"
-
-Oid LastOidProcessed = InvalidOid;
+#include "storage/smgr.h"
+#include "utils/acl.h"
+#include "utils/builtins.h"
+#include "utils/inval.h"
+#include "utils/lsyscache.h"
+#include "utils/rel.h"
+#include "utils/syscache.h"
+#include "utils/tqual.h"
-/*
- * Convert given string to a suitably quoted string constant,
- * and append it to the StringInfo buffer.
- * XXX Any MULTIBYTE considerations here?
- */
-static void
-quoteString(StringInfo buf, char *source)
-{
- char *current;
+static void checkRuleResultList(List *targetList, TupleDesc resultDesc,
+ bool isSelect);
+static bool setRuleCheckAsUser_walker(Node *node, Oid *context);
+static void setRuleCheckAsUser_Query(Query *qry, Oid userid);
- appendStringInfoChar(buf, '\'');
- for (current = source; *current; current++)
- {
- char ch = *current;
- if (ch == '\'' || ch == '\\')
- {
- appendStringInfoChar(buf, '\\');
- appendStringInfoChar(buf, ch);
- }
- else if (ch >= 0 && ch < ' ')
- appendStringInfo(buf, "\\%03o", (int) ch);
- else
- appendStringInfoChar(buf, ch);
- }
- appendStringInfoChar(buf, '\'');
-}
/*
* InsertRule -
- * takes the arguments and inserts them as attributes into the system
+ * takes the arguments and inserts them as a row into the system
* relation "pg_rewrite"
- *
- * MODS : changes the value of LastOidProcessed as a side
- * effect of inserting the rule tuple
- *
- * ARGS : rulname - name of the rule
- * evtype - one of RETRIEVE,REPLACE,DELETE,APPEND
- * evobj - name of relation
- * evslot - comma delimited list of slots
- * if null => multi-attr rule
- * evinstead - is an instead rule
- * actiontree - parsetree(s) of rule action
*/
static Oid
InsertRule(char *rulname,
int evtype,
- char *evobj,
- char *evslot,
- char *evqual,
+ Oid eventrel_oid,
+ AttrNumber evslot_index,
bool evinstead,
- char *actiontree)
+ Node *event_qual,
+ List *action,
+ bool replace)
{
- StringInfoData rulebuf;
- Relation eventrel;
- Oid eventrel_oid;
- AttrNumber evslot_index;
- char *is_instead = "f";
-
- eventrel = heap_openr(evobj, AccessShareLock);
- eventrel_oid = RelationGetRelid(eventrel);
+ char *evqual = nodeToString(event_qual);
+ char *actiontree = nodeToString((Node *) action);
+ int i;
+ Datum values[Natts_pg_rewrite];
+ char nulls[Natts_pg_rewrite];
+ char replaces[Natts_pg_rewrite];
+ NameData rname;
+ Relation pg_rewrite_desc;
+ HeapTuple tup,
+ oldtup;
+ Oid rewriteObjectId;
+ ObjectAddress myself,
+ referenced;
+ bool is_update = false;
/*
- * if the slotname is null, we know that this is a multi-attr rule
+ * Set up *nulls and *values arrays
*/
- if (evslot == NULL)
- evslot_index = -1;
- else
- evslot_index = attnameAttNum(eventrel, evslot);
- heap_close(eventrel, AccessShareLock);
+ MemSet(nulls, ' ', sizeof(nulls));
+
+ i = 0;
+ namestrcpy(&rname, rulname);
+ values[i++] = NameGetDatum(&rname); /* rulename */
+ values[i++] = ObjectIdGetDatum(eventrel_oid); /* ev_class */
+ values[i++] = Int16GetDatum(evslot_index); /* ev_attr */
+ values[i++] = CharGetDatum(evtype + '0'); /* ev_type */
+ values[i++] = CharGetDatum(RULE_FIRES_ON_ORIGIN); /* ev_enabled */
+ values[i++] = BoolGetDatum(evinstead); /* is_instead */
+ values[i++] = CStringGetTextDatum(evqual); /* ev_qual */
+ values[i++] = CStringGetTextDatum(actiontree); /* ev_action */
- if (evinstead)
- is_instead = "t";
+ /*
+ * Ready to store new pg_rewrite tuple
+ */
+ pg_rewrite_desc = heap_open(RewriteRelationId, RowExclusiveLock);
- if (evqual == NULL)
- evqual = "<>";
+ /*
+ * Check to see if we are replacing an existing tuple
+ */
+ oldtup = SearchSysCache(RULERELNAME,
+ ObjectIdGetDatum(eventrel_oid),
+ PointerGetDatum(rulname),
+ 0, 0);
- if (IsDefinedRewriteRule(rulname))
- elog(ERROR, "Attempt to insert rule '%s' failed: already exists",
- rulname);
+ if (HeapTupleIsValid(oldtup))
+ {
+ if (!replace)
+ ereport(ERROR,
+ (errcode(ERRCODE_DUPLICATE_OBJECT),
+ errmsg("rule \"%s\" for relation \"%s\" already exists",
+ rulname, get_rel_name(eventrel_oid))));
- initStringInfo(&rulebuf);
- appendStringInfo(&rulebuf,
- "INSERT INTO pg_rewrite (rulename, ev_type, ev_class, ev_attr, ev_action, ev_qual, is_instead) VALUES (");
- quoteString(&rulebuf, rulname);
- appendStringInfo(&rulebuf, ", %d::char, %u::oid, %d::int2, ",
- evtype, eventrel_oid, evslot_index);
- quoteString(&rulebuf, actiontree);
- appendStringInfo(&rulebuf, "::text, ");
- quoteString(&rulebuf, evqual);
- appendStringInfo(&rulebuf, "::text, '%s'::bool);",
- is_instead);
+ /*
+ * When replacing, we don't need to replace every attribute
+ */
+ MemSet(replaces, ' ', sizeof(replaces));
+ replaces[Anum_pg_rewrite_ev_attr - 1] = 'r';
+ replaces[Anum_pg_rewrite_ev_type - 1] = 'r';
+ replaces[Anum_pg_rewrite_is_instead - 1] = 'r';
+ replaces[Anum_pg_rewrite_ev_qual - 1] = 'r';
+ replaces[Anum_pg_rewrite_ev_action - 1] = 'r';
- pg_exec_query_dest(NameStr(rulebuf), None, true);
+ tup = heap_modifytuple(oldtup, RelationGetDescr(pg_rewrite_desc),
+ values, nulls, replaces);
- pfree(NameStr(rulebuf));
+ simple_heap_update(pg_rewrite_desc, &tup->t_self, tup);
- return LastOidProcessed;
-}
+ ReleaseSysCache(oldtup);
-/*
- * for now, event_object must be a single attribute
- */
-static void
-ValidateRule(int event_type,
- char *eobj_string,
- char *eslot_string,
- Node *event_qual,
- List **action,
- int is_instead,
- Oid event_attype)
-{
- if (((event_type == CMD_INSERT) || (event_type == CMD_DELETE)) &&
- eslot_string)
+ rewriteObjectId = HeapTupleGetOid(tup);
+ is_update = true;
+ }
+ else
{
- elog(ERROR,
- "rules not allowed for insert or delete events to an attribute");
+ tup = heap_formtuple(pg_rewrite_desc->rd_att, values, nulls);
+
+ rewriteObjectId = simple_heap_insert(pg_rewrite_desc, tup);
}
-#ifdef NOT_USED
+ /* Need to update indexes in either case */
+ CatalogUpdateIndexes(pg_rewrite_desc, tup);
+
+ heap_freetuple(tup);
+
+ /* If replacing, get rid of old dependencies and make new ones */
+ if (is_update)
+ deleteDependencyRecordsFor(RewriteRelationId, rewriteObjectId);
/*
- * on retrieve to class.attribute do instead nothing is converted to
- * 'on retrieve to class.attribute do instead retrieve (attribute =
- * NULL)' --- this is also a terrible hack that works well -- glass
+ * Install dependency on rule's relation to ensure it will go away on
+ * relation deletion. If the rule is ON SELECT, make the dependency
+ * implicit --- this prevents deleting a view's SELECT rule. Other kinds
+ * of rules can be AUTO.
*/
- if (is_instead && !*action && eslot_string && event_type == CMD_SELECT)
- {
- char *temp_buffer = (char *) palloc(strlen(template) + 80);
+ myself.classId = RewriteRelationId;
+ myself.objectId = rewriteObjectId;
+ myself.objectSubId = 0;
+
+ referenced.classId = RelationRelationId;
+ referenced.objectId = eventrel_oid;
+ referenced.objectSubId = 0;
+
+ recordDependencyOn(&myself, &referenced,
+ (evtype == CMD_SELECT) ? DEPENDENCY_INTERNAL : DEPENDENCY_AUTO);
- sprintf(temp_buffer, template, event_attype,
- get_typlen(event_attype), eslot_string,
- event_attype);
+ /*
+ * Also install dependencies on objects referenced in action and qual.
+ */
+ recordDependencyOnExpr(&myself, (Node *) action, NIL,
+ DEPENDENCY_NORMAL);
- *action = (List *) stringToNode(temp_buffer);
+ if (event_qual != NULL)
+ {
+ /* Find query containing OLD/NEW rtable entries */
+ Query *qry = (Query *) linitial(action);
- pfree(temp_buffer);
+ qry = getInsertSelectQuery(qry, NULL);
+ recordDependencyOnExpr(&myself, event_qual, qry->rtable,
+ DEPENDENCY_NORMAL);
}
-#endif
+
+ heap_close(pg_rewrite_desc, RowExclusiveLock);
+
+ return rewriteObjectId;
+}
+
+/*
+ * DefineRule
+ * Execute a CREATE RULE command.
+ */
+void
+DefineRule(RuleStmt *stmt, const char *queryString)
+{
+ List *actions;
+ Node *whereClause;
+ Oid relId;
+
+ /* Parse analysis ... */
+ transformRuleStmt(stmt, queryString, &actions, &whereClause);
+
+ /* ... find the relation ... */
+ relId = RangeVarGetRelid(stmt->relation, false);
+
+ /* ... and execute */
+ DefineQueryRewrite(stmt->rulename,
+ relId,
+ whereClause,
+ stmt->event,
+ stmt->instead,
+ stmt->replace,
+ actions);
}
+
+/*
+ * DefineQueryRewrite
+ * Create a rule
+ *
+ * This is essentially the same as DefineRule() except that the rule's
+ * action and qual have already been passed through parse analysis.
+ */
void
-DefineQueryRewrite(RuleStmt *stmt)
+DefineQueryRewrite(char *rulename,
+ Oid event_relid,
+ Node *event_qual,
+ CmdType event_type,
+ bool is_instead,
+ bool replace,
+ List *action)
{
- CmdType event_type = stmt->event;
- Attr *event_obj = stmt->object;
- Node *event_qual = stmt->whereClause;
- bool is_instead = stmt->instead;
- List *action = stmt->actions;
- Relation event_relation = NULL;
+ Relation event_relation;
Oid ruleId;
- Oid ev_relid = 0;
- char *eslot_string = NULL;
- int event_attno = 0;
- Oid event_attype = 0;
- char *actionP,
- *event_qualP;
- List *l;
+ int event_attno;
+ ListCell *l;
Query *query;
+ bool RelisBecomingView = false;
- /* ----------
- * The current rewrite handler is known to work on relation level
- * rules only. And for SELECT events, it expects one non-nothing
- * action that is instead and returns exactly a tuple of the
- * rewritten relation. This restricts SELECT rules to views.
- *
- * Jan
- * ----------
+ /*
+ * If we are installing an ON SELECT rule, we had better grab
+ * AccessExclusiveLock to ensure no SELECTs are currently running on the
+ * event relation. For other types of rules, it might be sufficient to
+ * grab ShareLock to lock out insert/update/delete actions. But for now,
+ * let's just grab AccessExclusiveLock all the time.
*/
- if (event_obj->attrs)
- elog(ERROR, "attribute level rules currently not supported");
+ event_relation = heap_open(event_relid, AccessExclusiveLock);
/*
- * eslot_string = strVal(lfirst(event_obj->attrs));
+ * Check user has permission to apply rules to this relation.
*/
- else
- eslot_string = NULL;
+ if (!pg_class_ownercheck(event_relid, GetUserId()))
+ aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
+ RelationGetRelationName(event_relation));
/*
* No rule actions that modify OLD or NEW
*/
- if (action != NIL)
- foreach(l, action)
+ foreach(l, action)
{
query = (Query *) lfirst(l);
- if (query->resultRelation == 1)
- {
- elog(NOTICE, "rule actions on OLD currently not supported");
- elog(ERROR, " use views or triggers instead");
- }
- if (query->resultRelation == 2)
- {
- elog(NOTICE, "rule actions on NEW currently not supported");
- elog(ERROR, " use triggers instead");
- }
+ if (query->resultRelation == 0)
+ continue;
+ /* Don't be fooled by INSERT/SELECT */
+ if (query != getInsertSelectQuery(query, NULL))
+ continue;
+ if (query->resultRelation == PRS2_OLD_VARNO)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("rule actions on OLD are not implemented"),
+ errhint("Use views or triggers instead.")));
+ if (query->resultRelation == PRS2_NEW_VARNO)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("rule actions on NEW are not implemented"),
+ errhint("Use triggers instead.")));
}
- /*
- * Rules ON SELECT are restricted to view definitions
- */
if (event_type == CMD_SELECT)
{
- TargetEntry *tle;
- Resdom *resdom;
- Form_pg_attribute attr;
- char *attname;
- int i;
- char expected_name[NAMEDATALEN + 5];
-
/*
+ * Rules ON SELECT are restricted to view definitions
+ *
* So there cannot be INSTEAD NOTHING, ...
*/
- if (length(action) == 0)
- {
- elog(NOTICE, "instead nothing rules on select currently not supported");
- elog(ERROR, " use views instead");
- }
+ if (list_length(action) == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("INSTEAD NOTHING rules on SELECT are not implemented"),
+ errhint("Use views instead.")));
/*
* ... there cannot be multiple actions, ...
*/
- if (length(action) > 1)
- elog(ERROR, "multiple action rules on select currently not supported");
+ if (list_length(action) > 1)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("multiple actions for rules on SELECT are not implemented")));
/*
* ... the one action must be a SELECT, ...
*/
- query = (Query *) lfirst(action);
- if (!is_instead || query->commandType != CMD_SELECT)
- elog(ERROR, "only instead-select rules currently supported on select");
+ query = (Query *) linitial(action);
+ if (!is_instead ||
+ query->commandType != CMD_SELECT ||
+ query->utilityStmt != NULL ||
+ query->intoClause != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("rules on SELECT must have action INSTEAD SELECT")));
+
+ /*
+ * ... there can be no rule qual, ...
+ */
if (event_qual != NULL)
- elog(ERROR, "event qualifications not supported for rules on select");
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("event qualifications are not implemented for rules on SELECT")));
/*
* ... the targetlist of the SELECT action must exactly match the
* event relation, ...
*/
- event_relation = heap_openr(event_obj->relname, AccessShareLock);
-
- if (event_relation->rd_att->natts != length(query->targetList))
- elog(ERROR, "select rules target list must match event relations structure");
-
- for (i = 1; i <= event_relation->rd_att->natts; i++)
- {
- tle = (TargetEntry *) nth(i - 1, query->targetList);
- resdom = tle->resdom;
- attr = event_relation->rd_att->attrs[i - 1];
- attname = pstrdup(NameStr(attr->attname));
-
- if (strcmp(resdom->resname, attname) != 0)
- elog(ERROR, "select rules target entry %d has different column name from %s", i, attname);
-
- if (attr->atttypid != resdom->restype)
- elog(ERROR, "select rules target entry %d has different type from attribute %s", i, attname);
-
- if (attr->atttypmod != resdom->restypmod)
- elog(ERROR, "select rules target entry %d has different size from attribute %s", i, attname);
- }
+ checkRuleResultList(query->targetList,
+ RelationGetDescr(event_relation),
+ true);
/*
* ... there must not be another ON SELECT rule already ...
*/
- if (event_relation->rd_rules != NULL)
+ if (!replace && event_relation->rd_rules != NULL)
{
+ int i;
+
for (i = 0; i < event_relation->rd_rules->numLocks; i++)
{
RewriteRule *rule;
rule = event_relation->rd_rules->rules[i];
if (rule->event == CMD_SELECT)
- elog(ERROR, "%s is already a view",
- RelationGetRelationName(event_relation));
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("\"%s\" is already a view",
+ RelationGetRelationName(event_relation))));
}
}
- heap_close(event_relation, AccessShareLock);
-
/*
- * LIMIT in view is not supported
+ * ... and finally the rule must be named _RETURN.
*/
- if (query->limitOffset != NULL || query->limitCount != NULL)
- elog(ERROR, "LIMIT clause not supported in views");
+ if (strcmp(rulename, ViewSelectRuleName) != 0)
+ {
+ /*
+ * In versions before 7.3, the expected name was _RETviewname. For
+ * backwards compatibility with old pg_dump output, accept that
+ * and silently change it to _RETURN. Since this is just a quick
+ * backwards-compatibility hack, limit the number of characters
+ * checked to a few less than NAMEDATALEN; this saves having to
+ * worry about where a multibyte character might have gotten
+ * truncated.
+ */
+ if (strncmp(rulename, "_RET", 4) != 0 ||
+ strncmp(rulename + 4, RelationGetRelationName(event_relation),
+ NAMEDATALEN - 4 - 4) != 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ errmsg("view rule for \"%s\" must be named \"%s\"",
+ RelationGetRelationName(event_relation),
+ ViewSelectRuleName)));
+ rulename = pstrdup(ViewSelectRuleName);
+ }
/*
- * DISTINCT on view is not supported
+ * Are we converting a relation to a view?
+ *
+ * If so, check that the relation is empty because the storage for the
+ * relation is going to be deleted. Also insist that the rel not have
+ * any triggers, indexes, or child tables.
*/
- if (query->uniqueFlag != NULL)
- elog(ERROR, "DISTINCT not supported in views");
-
+ if (event_relation->rd_rel->relkind != RELKIND_VIEW)
+ {
+ HeapScanDesc scanDesc;
+
+ scanDesc = heap_beginscan(event_relation, SnapshotNow, 0, NULL);
+ if (heap_getnext(scanDesc, ForwardScanDirection) != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("could not convert table \"%s\" to a view because it is not empty",
+ RelationGetRelationName(event_relation))));
+ heap_endscan(scanDesc);
+
+ if (event_relation->rd_rel->reltriggers != 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("could not convert table \"%s\" to a view because it has triggers",
+ RelationGetRelationName(event_relation)),
+ errhint("In particular, the table cannot be involved in any foreign key relationships.")));
+
+ if (event_relation->rd_rel->relhasindex)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("could not convert table \"%s\" to a view because it has indexes",
+ RelationGetRelationName(event_relation))));
+
+ if (event_relation->rd_rel->relhassubclass)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("could not convert table \"%s\" to a view because it has child tables",
+ RelationGetRelationName(event_relation))));
+
+ RelisBecomingView = true;
+ }
+ }
+ else
+ {
/*
- * ORDER BY in view is not supported
+ * For non-SELECT rules, a RETURNING list can appear in at most one of
+ * the actions ... and there can't be any RETURNING list at all in a
+ * conditional or non-INSTEAD rule. (Actually, there can be at most
+ * one RETURNING list across all rules on the same event, but it seems
+ * best to enforce that at rule expansion time.) If there is a
+ * RETURNING list, it must match the event relation.
*/
- if (query->sortClause != NIL)
- elog(ERROR, "ORDER BY not supported in views");
+ bool haveReturning = false;
- /*
- * ... and finally the rule must be named _RETviewname.
- */
- sprintf(expected_name, "_RET%s", event_obj->relname);
- if (strcmp(expected_name, stmt->rulename) != 0)
+ foreach(l, action)
{
- elog(ERROR, "view rule for %s must be named %s",
- event_obj->relname, expected_name);
+ query = (Query *) lfirst(l);
+
+ if (!query->returningList)
+ continue;
+ if (haveReturning)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot have multiple RETURNING lists in a rule")));
+ haveReturning = true;
+ if (event_qual != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("RETURNING lists are not supported in conditional rules")));
+ if (!is_instead)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("RETURNING lists are not supported in non-INSTEAD rules")));
+ checkRuleResultList(query->returningList,
+ RelationGetDescr(event_relation),
+ false);
}
}
/*
- * This rule is allowed - install it.
+ * This rule is allowed - prepare to install it.
*/
+ event_attno = -1;
- event_relation = heap_openr(event_obj->relname, AccessShareLock);
- ev_relid = RelationGetRelid(event_relation);
+ /* discard rule if it's null action and not INSTEAD; it's a no-op */
+ if (action != NIL || is_instead)
+ {
+ ruleId = InsertRule(rulename,
+ event_type,
+ event_relid,
+ event_attno,
+ is_instead,
+ event_qual,
+ action,
+ replace);
+
+ /*
+ * Set pg_class 'relhasrules' field TRUE for event relation. If
+ * appropriate, also modify the 'relkind' field to show that the
+ * relation is now a view.
+ *
+ * Important side effect: an SI notice is broadcast to force all
+ * backends (including me!) to update relcache entries with the new
+ * rule.
+ */
+ SetRelationRuleStatus(event_relid, true, RelisBecomingView);
+ }
- if (eslot_string == NULL)
+ /*
+ * IF the relation is becoming a view, delete the storage files associated
+ * with it. NB: we had better have AccessExclusiveLock to do this ...
+ *
+ * XXX what about getting rid of its TOAST table? For now, we don't.
+ */
+ if (RelisBecomingView)
{
- event_attno = -1;
- event_attype = -1; /* XXX - don't care */
+ ForkNumber forknum;
+
+ RelationOpenSmgr(event_relation);
+ for (forknum = 0; forknum <= MAX_FORKNUM; forknum++)
+ if (smgrexists(event_relation->rd_smgr, forknum))
+ smgrscheduleunlink(event_relation->rd_smgr, forknum,
+ event_relation->rd_istemp);
+ RelationCloseSmgr(event_relation);
}
- else
+
+ /* Close rel, but keep lock till commit... */
+ heap_close(event_relation, NoLock);
+}
+
+/*
+ * checkRuleResultList
+ * Verify that targetList produces output compatible with a tupledesc
+ *
+ * The targetList might be either a SELECT targetlist, or a RETURNING list;
+ * isSelect tells which. (This is mostly used for choosing error messages,
+ * but also we don't enforce column name matching for RETURNING.)
+ */
+static void
+checkRuleResultList(List *targetList, TupleDesc resultDesc, bool isSelect)
+{
+ ListCell *tllist;
+ int i;
+
+ i = 0;
+ foreach(tllist, targetList)
{
- event_attno = attnameAttNum(event_relation, eslot_string);
- event_attype = attnumTypeId(event_relation, event_attno);
+ TargetEntry *tle = (TargetEntry *) lfirst(tllist);
+ int32 tletypmod;
+ Form_pg_attribute attr;
+ char *attname;
+
+ /* resjunk entries may be ignored */
+ if (tle->resjunk)
+ continue;
+ i++;
+ if (i > resultDesc->natts)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ isSelect ?
+ errmsg("SELECT rule's target list has too many entries") :
+ errmsg("RETURNING list has too many entries")));
+
+ attr = resultDesc->attrs[i - 1];
+ attname = NameStr(attr->attname);
+
+ /*
+ * Disallow dropped columns in the relation. This won't happen in the
+ * cases we actually care about (namely creating a view via CREATE
+ * TABLE then CREATE RULE, or adding a RETURNING rule to a view).
+ * Trying to cope with it is much more trouble than it's worth,
+ * because we'd have to modify the rule to insert dummy NULLs at the
+ * right positions.
+ */
+ if (attr->attisdropped)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot convert relation containing dropped columns to view")));
+
+ if (isSelect && strcmp(tle->resname, attname) != 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ errmsg("SELECT rule's target entry %d has different column name from \"%s\"", i, attname)));
+
+ if (attr->atttypid != exprType((Node *) tle->expr))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ isSelect ?
+ errmsg("SELECT rule's target entry %d has different type from column \"%s\"",
+ i, attname) :
+ errmsg("RETURNING list's entry %d has different type from column \"%s\"",
+ i, attname)));
+
+ /*
+ * Allow typmods to be different only if one of them is -1, ie,
+ * "unspecified". This is necessary for cases like "numeric", where
+ * the table will have a filled-in default length but the select
+ * rule's expression will probably have typmod = -1.
+ */
+ tletypmod = exprTypmod((Node *) tle->expr);
+ if (attr->atttypmod != tletypmod &&
+ attr->atttypmod != -1 && tletypmod != -1)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ isSelect ?
+ errmsg("SELECT rule's target entry %d has different size from column \"%s\"",
+ i, attname) :
+ errmsg("RETURNING list's entry %d has different size from column \"%s\"",
+ i, attname)));
}
- heap_close(event_relation, AccessShareLock);
- /* fix bug about instead nothing */
- ValidateRule(event_type, event_obj->relname,
- eslot_string, event_qual, &action,
- is_instead, event_attype);
+ if (i != resultDesc->natts)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+ isSelect ?
+ errmsg("SELECT rule's target list has too few entries") :
+ errmsg("RETURNING list has too few entries")));
+}
- if (action == NULL)
+/*
+ * setRuleCheckAsUser
+ * Recursively scan a query or expression tree and set the checkAsUser
+ * field to the given userid in all rtable entries.
+ *
+ * Note: for a view (ON SELECT rule), the checkAsUser field of the *OLD*
+ * RTE entry will be overridden when the view rule is expanded, and the
+ * checkAsUser field of the *NEW* entry is irrelevant because that entry's
+ * requiredPerms bits will always be zero. However, for other types of rules
+ * it's important to set these fields to match the rule owner. So we just set
+ * them always.
+ */
+void
+setRuleCheckAsUser(Node *node, Oid userid)
+{
+ (void) setRuleCheckAsUser_walker(node, &userid);
+}
+
+static bool
+setRuleCheckAsUser_walker(Node *node, Oid *context)
+{
+ if (node == NULL)
+ return false;
+ if (IsA(node, Query))
{
- if (!is_instead)
- return; /* doesn't do anything */
+ setRuleCheckAsUser_Query((Query *) node, *context);
+ return false;
+ }
+ return expression_tree_walker(node, setRuleCheckAsUser_walker,
+ (void *) context);
+}
- event_qualP = nodeToString(event_qual);
+static void
+setRuleCheckAsUser_Query(Query *qry, Oid userid)
+{
+ ListCell *l;
- ruleId = InsertRule(stmt->rulename,
- event_type,
- event_obj->relname,
- eslot_string,
- event_qualP,
- true,
- "<>");
- prs2_addToRelation(ev_relid, ruleId, event_type, event_attno, TRUE,
- event_qual, NIL);
+ /* Set all the RTEs in this query node */
+ foreach(l, qry->rtable)
+ {
+ RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
+ if (rte->rtekind == RTE_SUBQUERY)
+ {
+ /* Recurse into subquery in FROM */
+ setRuleCheckAsUser_Query(rte->subquery, userid);
+ }
+ else
+ rte->checkAsUser = userid;
}
- else
+
+ /* Recurse into subquery-in-WITH */
+ foreach(l, qry->cteList)
{
- event_qualP = nodeToString(event_qual);
- actionP = nodeToString(action);
+ CommonTableExpr *cte = (CommonTableExpr *) lfirst(l);
- ruleId = InsertRule(stmt->rulename,
- event_type,
- event_obj->relname,
- eslot_string,
- event_qualP,
- is_instead,
- actionP);
+ setRuleCheckAsUser_Query((Query *) cte->ctequery, userid);
+ }
+
+ /* If there are sublinks, search for them and process their RTEs */
+ if (qry->hasSubLinks)
+ query_tree_walker(qry, setRuleCheckAsUser_walker, (void *) &userid,
+ QTW_IGNORE_RC_SUBQUERIES);
+}
+
+
+/*
+ * Change the firing semantics of an existing rule.
+ */
+void
+EnableDisableRule(Relation rel, const char *rulename,
+ char fires_when)
+{
+ Relation pg_rewrite_desc;
+ Oid owningRel = RelationGetRelid(rel);
+ Oid eventRelationOid;
+ HeapTuple ruletup;
+ bool changed = false;
+
+ /*
+ * Find the rule tuple to change.
+ */
+ pg_rewrite_desc = heap_open(RewriteRelationId, RowExclusiveLock);
+ ruletup = SearchSysCacheCopy(RULERELNAME,
+ ObjectIdGetDatum(owningRel),
+ PointerGetDatum(rulename),
+ 0, 0);
+ if (!HeapTupleIsValid(ruletup))
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("rule \"%s\" for relation \"%s\" does not exist",
+ rulename, get_rel_name(owningRel))));
+
+ /*
+ * Verify that the user has appropriate permissions.
+ */
+ eventRelationOid = ((Form_pg_rewrite) GETSTRUCT(ruletup))->ev_class;
+ Assert(eventRelationOid == owningRel);
+ if (!pg_class_ownercheck(eventRelationOid, GetUserId()))
+ aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
+ get_rel_name(eventRelationOid));
+
+ /*
+ * Change ev_enabled if it is different from the desired new state.
+ */
+ if (DatumGetChar(((Form_pg_rewrite) GETSTRUCT(ruletup))->ev_enabled) !=
+ fires_when)
+ {
+ ((Form_pg_rewrite) GETSTRUCT(ruletup))->ev_enabled =
+ CharGetDatum(fires_when);
+ simple_heap_update(pg_rewrite_desc, &ruletup->t_self, ruletup);
- /* what is the max size of type text? XXX -- glass */
- if (length(action) > 15)
- elog(ERROR, "max # of actions exceeded");
- prs2_addToRelation(ev_relid, ruleId, event_type, event_attno,
- is_instead, event_qual, action);
+ /* keep system catalog indexes current */
+ CatalogUpdateIndexes(pg_rewrite_desc, ruletup);
+
+ changed = true;
}
+
+ heap_freetuple(ruletup);
+ heap_close(pg_rewrite_desc, RowExclusiveLock);
+
+ /*
+ * If we changed anything, broadcast a SI inval message to force each
+ * backend (including our own!) to rebuild relation's relcache entry.
+ * Otherwise they will fail to apply the change promptly.
+ */
+ if (changed)
+ CacheInvalidateRelcache(rel);
}
+
+
+/*
+ * Rename an existing rewrite rule.
+ *
+ * This is unused code at the moment. Note that it lacks a permissions check.
+ */
+#ifdef NOT_USED
+void
+RenameRewriteRule(Oid owningRel, const char *oldName,
+ const char *newName)
+{
+ Relation pg_rewrite_desc;
+ HeapTuple ruletup;
+
+ pg_rewrite_desc = heap_open(RewriteRelationId, RowExclusiveLock);
+
+ ruletup = SearchSysCacheCopy(RULERELNAME,
+ ObjectIdGetDatum(owningRel),
+ PointerGetDatum(oldName),
+ 0, 0);
+ if (!HeapTupleIsValid(ruletup))
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("rule \"%s\" for relation \"%s\" does not exist",
+ oldName, get_rel_name(owningRel))));
+
+ /* should not already exist */
+ if (IsDefinedRewriteRule(owningRel, newName))
+ ereport(ERROR,
+ (errcode(ERRCODE_DUPLICATE_OBJECT),
+ errmsg("rule \"%s\" for relation \"%s\" already exists",
+ newName, get_rel_name(owningRel))));
+
+ namestrcpy(&(((Form_pg_rewrite) GETSTRUCT(ruletup))->rulename), newName);
+
+ simple_heap_update(pg_rewrite_desc, &ruletup->t_self, ruletup);
+
+ /* keep system catalog indexes current */
+ CatalogUpdateIndexes(pg_rewrite_desc, ruletup);
+
+ heap_freetuple(ruletup);
+ heap_close(pg_rewrite_desc, RowExclusiveLock);
+}
+
+#endif
projects / postgresql / blobdiff