utility.c

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

					 * but now it's done inside performDeletion().
					 */
				}
			}
			break;

		case T_TruncateStmt:
			{
				TruncateStmt *stmt = (TruncateStmt *) parsetree;

				ExecuteTruncate(stmt->relations);
			}
			break;

		case T_CommentStmt:
			CommentObject((CommentStmt *) parsetree);
			break;

		case T_CopyStmt:
			DoCopy((CopyStmt *) parsetree);
			break;

		case T_PrepareStmt:
			PrepareQuery((PrepareStmt *) parsetree);
			break;

		case T_ExecuteStmt:
			ExecuteQuery((ExecuteStmt *) parsetree, dest, completionTag);
			break;

		case T_DeallocateStmt:
			DeallocateQuery((DeallocateStmt *) parsetree);
			break;

			/*
			 * schema
			 */
		case T_RenameStmt:
			ExecRenameStmt((RenameStmt *) parsetree);
			break;

		case T_AlterObjectSchemaStmt:
			ExecAlterObjectSchemaStmt((AlterObjectSchemaStmt *) parsetree);
			break;

		case T_AlterOwnerStmt:
			ExecAlterOwnerStmt((AlterOwnerStmt *) parsetree);
			break;

		case T_AlterTableStmt:
			AlterTable((AlterTableStmt *) parsetree);
			break;

		case T_AlterDomainStmt:
			{
				AlterDomainStmt *stmt = (AlterDomainStmt *) parsetree;

				/*
				 * Some or all of these functions are recursive to cover
				 * inherited things, so permission checks are done there.
				 */
				switch (stmt->subtype)
				{
					case 'T':	/* ALTER DOMAIN DEFAULT */

						/*
						 * Recursively alter column default for table and, if
						 * requested, for descendants
						 */
						AlterDomainDefault(stmt->typename,
										   stmt->def);
						break;
					case 'N':	/* ALTER DOMAIN DROP NOT NULL */
						AlterDomainNotNull(stmt->typename,
										   false);
						break;
					case 'O':	/* ALTER DOMAIN SET NOT NULL */
						AlterDomainNotNull(stmt->typename,
										   true);
						break;
					case 'C':	/* ADD CONSTRAINT */
						AlterDomainAddConstraint(stmt->typename,
												 stmt->def);
						break;
					case 'X':	/* DROP CONSTRAINT */
						AlterDomainDropConstraint(stmt->typename,
												  stmt->name,
												  stmt->behavior);
						break;
					default:	/* oops */
						elog(ERROR, "unrecognized alter domain type: %d",
							 (int) stmt->subtype);
						break;
				}
			}
			break;

		case T_GrantStmt:
			ExecuteGrantStmt((GrantStmt *) parsetree);
			break;

		case T_GrantRoleStmt:
			GrantRole((GrantRoleStmt *) parsetree);
			break;

			/*
			 * ******************************** object creation / destruction ********************************
			 *
			 */
		case T_DefineStmt:
			{
				DefineStmt *stmt = (DefineStmt *) parsetree;

				switch (stmt->kind)
				{
					case OBJECT_AGGREGATE:
						DefineAggregate(stmt->defnames, stmt->definition);
						break;
					case OBJECT_OPERATOR:
						DefineOperator(stmt->defnames, stmt->definition);
						break;
					case OBJECT_TYPE:
						DefineType(stmt->defnames, stmt->definition);
						break;
					default:
						elog(ERROR, "unrecognized define stmt type: %d",
							 (int) stmt->kind);
						break;
				}
			}
			break;

		case T_CompositeTypeStmt:		/* CREATE TYPE (composite) */
			{
				CompositeTypeStmt *stmt = (CompositeTypeStmt *) parsetree;

				DefineCompositeType(stmt->typevar, stmt->coldeflist);
			}
			break;

		case T_ViewStmt:		/* CREATE VIEW */
			{
				ViewStmt   *stmt = (ViewStmt *) parsetree;

				DefineView(stmt->view, stmt->query, stmt->replace);
			}
			break;

		case T_CreateFunctionStmt:		/* CREATE FUNCTION */
			CreateFunction((CreateFunctionStmt *) parsetree);
			break;

		case T_AlterFunctionStmt:		/* ALTER FUNCTION */
			AlterFunction((AlterFunctionStmt *) parsetree);
			break;

		case T_IndexStmt:		/* CREATE INDEX */
			{
				IndexStmt  *stmt = (IndexStmt *) parsetree;

				CheckRelationOwnership(stmt->relation, true);

				DefineIndex(stmt->relation,		/* relation */
							stmt->idxname,		/* index name */
							InvalidOid, /* no predefined OID */
							stmt->accessMethod, /* am name */
							stmt->tableSpace,
							stmt->indexParams,	/* parameters */
							(Expr *) stmt->whereClause,
							stmt->rangetable,
							stmt->unique,
							stmt->primary,
							stmt->isconstraint,
							false,		/* is_alter_table */
							true,		/* check_rights */
							false,		/* skip_build */
							false);		/* quiet */
			}
			break;

		case T_RuleStmt:		/* CREATE RULE */
			DefineQueryRewrite((RuleStmt *) parsetree);
			break;

		case T_CreateSeqStmt:
			DefineSequence((CreateSeqStmt *) parsetree);
			break;

		case T_AlterSeqStmt:
			AlterSequence((AlterSeqStmt *) parsetree);
			break;

		case T_RemoveAggrStmt:
			RemoveAggregate((RemoveAggrStmt *) parsetree);
			break;

		case T_RemoveFuncStmt:
			RemoveFunction((RemoveFuncStmt *) parsetree);
			break;

		case T_RemoveOperStmt:
			RemoveOperator((RemoveOperStmt *) parsetree);
			break;

		case T_CreatedbStmt:
			createdb((CreatedbStmt *) parsetree);
			break;

		case T_AlterDatabaseStmt:
			AlterDatabase((AlterDatabaseStmt *) parsetree);
			break;

		case T_AlterDatabaseSetStmt:
			AlterDatabaseSet((AlterDatabaseSetStmt *) parsetree);
			break;

		case T_DropdbStmt:
			{
				DropdbStmt *stmt = (DropdbStmt *) parsetree;

				dropdb(stmt->dbname);
			}
			break;

			/* Query-level asynchronous notification */
		case T_NotifyStmt:
			{
				NotifyStmt *stmt = (NotifyStmt *) parsetree;

				Async_Notify(stmt->relation->relname);
			}
			break;

		case T_ListenStmt:
			{
				ListenStmt *stmt = (ListenStmt *) parsetree;

				Async_Listen(stmt->relation->relname);
			}
			break;

		case T_UnlistenStmt:
			{
				UnlistenStmt *stmt = (UnlistenStmt *) parsetree;

				Async_Unlisten(stmt->relation->relname);
			}
			break;

		case T_LoadStmt:
			{
				LoadStmt   *stmt = (LoadStmt *) parsetree;

				if (!superuser())
					ereport(ERROR,
							(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
							 errmsg("must be superuser to do LOAD")));
				closeAllVfds(); /* probably not necessary... */
				load_file(stmt->filename);
			}
			break;

		case T_ClusterStmt:
			cluster((ClusterStmt *) parsetree);
			break;

		case T_VacuumStmt:
			vacuum((VacuumStmt *) parsetree, NIL);
			break;

		case T_ExplainStmt:
			ExplainQuery((ExplainStmt *) parsetree, dest);
			break;

		case T_VariableSetStmt:
			{
				VariableSetStmt *n = (VariableSetStmt *) parsetree;

				/*
				 * Special cases for special SQL syntax that effectively sets
				 * more than one variable per statement.
				 */
				if (strcmp(n->name, "TRANSACTION") == 0)
				{
					ListCell   *head;

					foreach(head, n->args)
					{
						DefElem    *item = (DefElem *) lfirst(head);

						if (strcmp(item->defname, "transaction_isolation") == 0)
							SetPGVariable("transaction_isolation",
										  list_make1(item->arg), n->is_local);
						else if (strcmp(item->defname, "transaction_read_only") == 0)
							SetPGVariable("transaction_read_only",
										  list_make1(item->arg), n->is_local);
					}
				}
				else if (strcmp(n->name, "SESSION CHARACTERISTICS") == 0)
				{
					ListCell   *head;

					foreach(head, n->args)
					{
						DefElem    *item = (DefElem *) lfirst(head);

						if (strcmp(item->defname, "transaction_isolation") == 0)
							SetPGVariable("default_transaction_isolation",
										  list_make1(item->arg), n->is_local);
						else if (strcmp(item->defname, "transaction_read_only") == 0)
							SetPGVariable("default_transaction_read_only",
										  list_make1(item->arg), n->is_local);
					}
				}
				else
					SetPGVariable(n->name, n->args, n->is_local);
			}
			break;

		case T_VariableShowStmt:
			{
				VariableShowStmt *n = (VariableShowStmt *) parsetree;

				GetPGVariable(n->name, dest);
			}
			break;

		case T_VariableResetStmt:
			{
				VariableResetStmt *n = (VariableResetStmt *) parsetree;

				ResetPGVariable(n->name);
			}
			break;

		case T_CreateTrigStmt:
			CreateTrigger((CreateTrigStmt *) parsetree, false);
			break;

		case T_DropPropertyStmt:
			{
				DropPropertyStmt *stmt = (DropPropertyStmt *) parsetree;
				Oid			relId;

				relId = RangeVarGetRelid(stmt->relation, false);

				switch (stmt->removeType)
				{
					case OBJECT_RULE:
						/* RemoveRewriteRule checks permissions */
						RemoveRewriteRule(relId, stmt->property,
										  stmt->behavior);
						break;
					case OBJECT_TRIGGER:
						/* DropTrigger checks permissions */
						DropTrigger(relId, stmt->property,
									stmt->behavior);
						break;
					default:
						elog(ERROR, "unrecognized object type: %d",
							 (int) stmt->removeType);
						break;
				}
			}
			break;

		case T_CreatePLangStmt:
			CreateProceduralLanguage((CreatePLangStmt *) parsetree);
			break;

		case T_DropPLangStmt:
			DropProceduralLanguage((DropPLangStmt *) parsetree);
			break;

			/*
			 * ******************************** DOMAIN statements ****
			 */
		case T_CreateDomainStmt:
			DefineDomain((CreateDomainStmt *) parsetree);
			break;

			/*
			 * ******************************** ROLE statements ****
			 */
		case T_CreateRoleStmt:
			CreateRole((CreateRoleStmt *) parsetree);
			break;

		case T_AlterRoleStmt:
			AlterRole((AlterRoleStmt *) parsetree);
			break;

		case T_AlterRoleSetStmt:
			AlterRoleSet((AlterRoleSetStmt *) parsetree);
			break;

		case T_DropRoleStmt:
			DropRole((DropRoleStmt *) parsetree);
			break;

		case T_LockStmt:
			LockTableCommand((LockStmt *) parsetree);
			break;

		case T_ConstraintsSetStmt:
			AfterTriggerSetState((ConstraintsSetStmt *) parsetree);
			break;

		case T_CheckPointStmt:
			if (!superuser())
				ereport(ERROR,
						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
						 errmsg("must be superuser to do CHECKPOINT")));
			RequestCheckpoint(true, false);
			break;

		case T_ReindexStmt:
			{
				ReindexStmt *stmt = (ReindexStmt *) parsetree;

				switch (stmt->kind)
				{
					case OBJECT_INDEX:
						ReindexIndex(stmt->relation);
						break;
					case OBJECT_TABLE:
						ReindexTable(stmt->relation);
						break;
					case OBJECT_DATABASE:
						ReindexDatabase(stmt->name,
										stmt->do_system, stmt->do_user);
						break;
					default:
						elog(ERROR, "unrecognized object type: %d",
							 (int) stmt->kind);
						break;
				}
				break;
			}
			break;

		case T_CreateConversionStmt:
			CreateConversionCommand((CreateConversionStmt *) parsetree);
			break;

		case T_CreateCastStmt:
			CreateCast((CreateCastStmt *) parsetree);
			break;

		case T_DropCastStmt:
			DropCast((DropCastStmt *) parsetree);
			break;

		case T_CreateOpClassStmt:
			DefineOpClass((CreateOpClassStmt *) parsetree);
			break;

		case T_RemoveOpClassStmt:
			RemoveOpClass((RemoveOpClassStmt *) parsetree);
			break;

		default:
			elog(ERROR, "unrecognized node type: %d",
				 (int) nodeTag(parsetree));
			break;
	}
}

/*
 * UtilityReturnsTuples
 *		Return "true" if this utility statement will send output to the
 *		destination.
 *
 * Generally, there should be a case here for each case in ProcessUtility
 * where "dest" is passed on.
 */
bool
UtilityReturnsTuples(Node *parsetree)
{
	switch (nodeTag(parsetree))
	{
		case T_FetchStmt:
			{
				FetchStmt  *stmt = (FetchStmt *) parsetree;
				Portal		portal;

				if (stmt->ismove)
					return false;
				portal = GetPortalByName(stmt->portalname);
				if (!PortalIsValid(portal))
					return false;		/* not our business to raise error */
				return portal->tupDesc ? true : false;
			}

		case T_ExecuteStmt:
			{
				ExecuteStmt *stmt = (ExecuteStmt *) parsetree;
				PreparedStatement *entry;

				if (stmt->into)
					return false;
				entry = FetchPreparedStatement(stmt->name, false);
				if (!entry)
					return false;		/* not our business to raise error */
				switch (ChoosePortalStrategy(entry->query_list))
				{
					case PORTAL_ONE_SELECT:
						return true;
					case PORTAL_UTIL_SELECT:
						return true;
					case PORTAL_MULTI_QUERY:
						/* will not return tuples */
						break;
				}
				return false;
			}

		case T_ExplainStmt:
			return true;

		case T_VariableShowStmt:
			return true;

		default:
			return false;
	}
}

/*
 * UtilityTupleDescriptor
 *		Fetch the actual output tuple descriptor for a utility statement
 *		for which UtilityReturnsTuples() previously returned "true".
 *
 * The returned descriptor is created in (or copied into) the current memory
 * context.
 */
TupleDesc
UtilityTupleDescriptor(Node *parsetree)
{
	switch (nodeTag(parsetree))
	{
		case T_FetchStmt:
			{
				FetchStmt  *stmt = (FetchStmt *) parsetree;
				Portal		portal;

				if (stmt->ismove)
					return NULL;
				portal = GetPortalByName(stmt->portalname);
				if (!PortalIsValid(portal))
					return NULL;	/* not our business to raise error */
				return CreateTupleDescCopy(portal->tupDesc);
			}

		case T_ExecuteStmt:
			{
				ExecuteStmt *stmt = (ExecuteStmt *) parsetree;
				PreparedStatement *entry;

				if (stmt->into)
					return NULL;
				entry = FetchPreparedStatement(stmt->name, false);
				if (!entry)
					return NULL;	/* not our business to raise error */
				return FetchPreparedStatementResultDesc(entry);
			}

		case T_ExplainStmt:
			return ExplainResultDesc((ExplainStmt *) parsetree);

		case T_VariableShowStmt:
			{
				VariableShowStmt *n = (VariableShowStmt *) parsetree;

				return GetPGVariableResultDesc(n->name);
			}

		default:
			return NULL;
	}
}


/*
 * CreateCommandTag