dependency.c

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

		case AttrDefaultRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_DEFAULT;

		case LanguageRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_LANGUAGE;

		case OperatorRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_OPERATOR;

		case OperatorClassRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_OPCLASS;

		case RewriteRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_REWRITE;

		case TriggerRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_TRIGGER;

		case NamespaceRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_SCHEMA;

		case AuthIdRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_ROLE;

		case DatabaseRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_DATABASE;

		case TableSpaceRelationId:
			Assert(object->objectSubId == 0);
			return OCLASS_TBLSPACE;
	}

	/* shouldn't get here */
	elog(ERROR, "unrecognized object class: %u", object->classId);
	return OCLASS_CLASS;		/* keep compiler quiet */
}

/*
 * getObjectDescription: build an object description for messages
 *
 * The result is a palloc'd string.
 */
char *
getObjectDescription(const ObjectAddress *object)
{
	StringInfoData buffer;

	initStringInfo(&buffer);

	switch (getObjectClass(object))
	{
		case OCLASS_CLASS:
			getRelationDescription(&buffer, object->objectId);
			if (object->objectSubId != 0)
				appendStringInfo(&buffer, _(" column %s"),
								 get_relid_attribute_name(object->objectId,
													   object->objectSubId));
			break;

		case OCLASS_PROC:
			appendStringInfo(&buffer, _("function %s"),
							 format_procedure(object->objectId));
			break;

		case OCLASS_TYPE:
			appendStringInfo(&buffer, _("type %s"),
							 format_type_be(object->objectId));
			break;

		case OCLASS_CAST:
			{
				Relation	castDesc;
				ScanKeyData skey[1];
				SysScanDesc rcscan;
				HeapTuple	tup;
				Form_pg_cast castForm;

				castDesc = heap_open(CastRelationId, AccessShareLock);

				ScanKeyInit(&skey[0],
							ObjectIdAttributeNumber,
							BTEqualStrategyNumber, F_OIDEQ,
							ObjectIdGetDatum(object->objectId));

				rcscan = systable_beginscan(castDesc, CastOidIndexId, true,
											SnapshotNow, 1, skey);

				tup = systable_getnext(rcscan);

				if (!HeapTupleIsValid(tup))
					elog(ERROR, "could not find tuple for cast %u",
						 object->objectId);

				castForm = (Form_pg_cast) GETSTRUCT(tup);

				appendStringInfo(&buffer, _("cast from %s to %s"),
								 format_type_be(castForm->castsource),
								 format_type_be(castForm->casttarget));

				systable_endscan(rcscan);
				heap_close(castDesc, AccessShareLock);
				break;
			}

		case OCLASS_CONSTRAINT:
			{
				Relation	conDesc;
				ScanKeyData skey[1];
				SysScanDesc rcscan;
				HeapTuple	tup;
				Form_pg_constraint con;

				conDesc = heap_open(ConstraintRelationId, AccessShareLock);

				ScanKeyInit(&skey[0],
							ObjectIdAttributeNumber,
							BTEqualStrategyNumber, F_OIDEQ,
							ObjectIdGetDatum(object->objectId));

				rcscan = systable_beginscan(conDesc, ConstraintOidIndexId, true,
											SnapshotNow, 1, skey);

				tup = systable_getnext(rcscan);

				if (!HeapTupleIsValid(tup))
					elog(ERROR, "could not find tuple for constraint %u",
						 object->objectId);

				con = (Form_pg_constraint) GETSTRUCT(tup);

				if (OidIsValid(con->conrelid))
				{
					appendStringInfo(&buffer, _("constraint %s on "),
									 NameStr(con->conname));
					getRelationDescription(&buffer, con->conrelid);
				}
				else
				{
					appendStringInfo(&buffer, _("constraint %s"),
									 NameStr(con->conname));
				}

				systable_endscan(rcscan);
				heap_close(conDesc, AccessShareLock);
				break;
			}

		case OCLASS_CONVERSION:
			{
				HeapTuple	conTup;

				conTup = SearchSysCache(CONOID,
										ObjectIdGetDatum(object->objectId),
										0, 0, 0);
				if (!HeapTupleIsValid(conTup))
					elog(ERROR, "cache lookup failed for conversion %u",
						 object->objectId);
				appendStringInfo(&buffer, _("conversion %s"),
				 NameStr(((Form_pg_conversion) GETSTRUCT(conTup))->conname));
				ReleaseSysCache(conTup);
				break;
			}

		case OCLASS_DEFAULT:
			{
				Relation	attrdefDesc;
				ScanKeyData skey[1];
				SysScanDesc adscan;
				HeapTuple	tup;
				Form_pg_attrdef attrdef;
				ObjectAddress colobject;

				attrdefDesc = heap_open(AttrDefaultRelationId, AccessShareLock);

				ScanKeyInit(&skey[0],
							ObjectIdAttributeNumber,
							BTEqualStrategyNumber, F_OIDEQ,
							ObjectIdGetDatum(object->objectId));

				adscan = systable_beginscan(attrdefDesc, AttrDefaultOidIndexId,
											true, SnapshotNow, 1, skey);

				tup = systable_getnext(adscan);

				if (!HeapTupleIsValid(tup))
					elog(ERROR, "could not find tuple for attrdef %u",
						 object->objectId);

				attrdef = (Form_pg_attrdef) GETSTRUCT(tup);

				colobject.classId = RelationRelationId;
				colobject.objectId = attrdef->adrelid;
				colobject.objectSubId = attrdef->adnum;

				appendStringInfo(&buffer, _("default for %s"),
								 getObjectDescription(&colobject));

				systable_endscan(adscan);
				heap_close(attrdefDesc, AccessShareLock);
				break;
			}

		case OCLASS_LANGUAGE:
			{
				HeapTuple	langTup;

				langTup = SearchSysCache(LANGOID,
										 ObjectIdGetDatum(object->objectId),
										 0, 0, 0);
				if (!HeapTupleIsValid(langTup))
					elog(ERROR, "cache lookup failed for language %u",
						 object->objectId);
				appendStringInfo(&buffer, _("language %s"),
				  NameStr(((Form_pg_language) GETSTRUCT(langTup))->lanname));
				ReleaseSysCache(langTup);
				break;
			}

		case OCLASS_OPERATOR:
			appendStringInfo(&buffer, _("operator %s"),
							 format_operator(object->objectId));
			break;

		case OCLASS_OPCLASS:
			{
				HeapTuple	opcTup;
				Form_pg_opclass opcForm;
				HeapTuple	amTup;
				Form_pg_am	amForm;
				char	   *nspname;

				opcTup = SearchSysCache(CLAOID,
										ObjectIdGetDatum(object->objectId),
										0, 0, 0);
				if (!HeapTupleIsValid(opcTup))
					elog(ERROR, "cache lookup failed for opclass %u",
						 object->objectId);
				opcForm = (Form_pg_opclass) GETSTRUCT(opcTup);

				amTup = SearchSysCache(AMOID,
									   ObjectIdGetDatum(opcForm->opcamid),
									   0, 0, 0);
				if (!HeapTupleIsValid(amTup))
					elog(ERROR, "cache lookup failed for access method %u",
						 opcForm->opcamid);
				amForm = (Form_pg_am) GETSTRUCT(amTup);

				/* Qualify the name if not visible in search path */
				if (OpclassIsVisible(object->objectId))
					nspname = NULL;
				else
					nspname = get_namespace_name(opcForm->opcnamespace);

				appendStringInfo(&buffer, _("operator class %s for access method %s"),
								 quote_qualified_identifier(nspname,
												  NameStr(opcForm->opcname)),
								 NameStr(amForm->amname));

				ReleaseSysCache(amTup);
				ReleaseSysCache(opcTup);
				break;
			}

		case OCLASS_REWRITE:
			{
				Relation	ruleDesc;
				ScanKeyData skey[1];
				SysScanDesc rcscan;
				HeapTuple	tup;
				Form_pg_rewrite rule;

				ruleDesc = heap_open(RewriteRelationId, AccessShareLock);

				ScanKeyInit(&skey[0],
							ObjectIdAttributeNumber,
							BTEqualStrategyNumber, F_OIDEQ,
							ObjectIdGetDatum(object->objectId));

				rcscan = systable_beginscan(ruleDesc, RewriteOidIndexId, true,
											SnapshotNow, 1, skey);

				tup = systable_getnext(rcscan);

				if (!HeapTupleIsValid(tup))
					elog(ERROR, "could not find tuple for rule %u",
						 object->objectId);

				rule = (Form_pg_rewrite) GETSTRUCT(tup);

				appendStringInfo(&buffer, _("rule %s on "),
								 NameStr(rule->rulename));
				getRelationDescription(&buffer, rule->ev_class);

				systable_endscan(rcscan);
				heap_close(ruleDesc, AccessShareLock);
				break;
			}

		case OCLASS_TRIGGER:
			{
				Relation	trigDesc;
				ScanKeyData skey[1];
				SysScanDesc tgscan;
				HeapTuple	tup;
				Form_pg_trigger trig;

				trigDesc = heap_open(TriggerRelationId, AccessShareLock);

				ScanKeyInit(&skey[0],
							ObjectIdAttributeNumber,
							BTEqualStrategyNumber, F_OIDEQ,
							ObjectIdGetDatum(object->objectId));

				tgscan = systable_beginscan(trigDesc, TriggerOidIndexId, true,
											SnapshotNow, 1, skey);

				tup = systable_getnext(tgscan);

				if (!HeapTupleIsValid(tup))
					elog(ERROR, "could not find tuple for trigger %u",
						 object->objectId);

				trig = (Form_pg_trigger) GETSTRUCT(tup);

				appendStringInfo(&buffer, _("trigger %s on "),
								 NameStr(trig->tgname));
				getRelationDescription(&buffer, trig->tgrelid);

				systable_endscan(tgscan);
				heap_close(trigDesc, AccessShareLock);
				break;
			}

		case OCLASS_SCHEMA:
			{
				char	   *nspname;

				nspname = get_namespace_name(object->objectId);
				if (!nspname)
					elog(ERROR, "cache lookup failed for namespace %u",
						 object->objectId);
				appendStringInfo(&buffer, _("schema %s"), nspname);
				break;
			}

		case OCLASS_ROLE:
			{
				appendStringInfo(&buffer, _("role %s"),
								 GetUserNameFromId(object->objectId));
				break;
			}

		case OCLASS_DATABASE:
			{
				char	   *datname;

				datname = get_database_name(object->objectId);
				if (!datname)
					elog(ERROR, "cache lookup failed for database %u",
						 object->objectId);
				appendStringInfo(&buffer, _("database %s"), datname);
				break;
			}

		case OCLASS_TBLSPACE:
			{
				char	   *tblspace;

				tblspace = get_tablespace_name(object->objectId);
				if (!tblspace)
					elog(ERROR, "cache lookup failed for tablespace %u",
						 object->objectId);
				appendStringInfo(&buffer, _("tablespace %s"), tblspace);
				break;
			}

		default:
			appendStringInfo(&buffer, "unrecognized object %u %u %d",
							 object->classId,
							 object->objectId,
							 object->objectSubId);
			break;
	}

	return buffer.data;
}

/*
 * subroutine for getObjectDescription: describe a relation
 */
static void
getRelationDescription(StringInfo buffer, Oid relid)
{
	HeapTuple	relTup;
	Form_pg_class relForm;
	char	   *nspname;
	char	   *relname;

	relTup = SearchSysCache(RELOID,
							ObjectIdGetDatum(relid),
							0, 0, 0);
	if (!HeapTupleIsValid(relTup))
		elog(ERROR, "cache lookup failed for relation %u", relid);
	relForm = (Form_pg_class) GETSTRUCT(relTup);

	/* Qualify the name if not visible in search path */
	if (RelationIsVisible(relid))
		nspname = NULL;
	else
		nspname = get_namespace_name(relForm->relnamespace);

	relname = quote_qualified_identifier(nspname, NameStr(relForm->relname));

	switch (relForm->relkind)
	{
		case RELKIND_RELATION:
			appendStringInfo(buffer, _("table %s"),
							 relname);
			break;
		case RELKIND_INDEX:
			appendStringInfo(buffer, _("index %s"),
							 relname);
			break;
		case RELKIND_SPECIAL:
			appendStringInfo(buffer, _("special system relation %s"),
							 relname);
			break;
		case RELKIND_SEQUENCE:
			appendStringInfo(buffer, _("sequence %s"),
							 relname);
			break;
		case RELKIND_UNCATALOGED:
			appendStringInfo(buffer, _("uncataloged table %s"),
							 relname);
			break;
		case RELKIND_TOASTVALUE:
			appendStringInfo(buffer, _("toast table %s"),
							 relname);
			break;
		case RELKIND_VIEW:
			appendStringInfo(buffer, _("view %s"),
							 relname);
			break;
		case RELKIND_COMPOSITE_TYPE:
			appendStringInfo(buffer, _("composite type %s"),
							 relname);
			break;
		default:
			/* shouldn't get here */
			appendStringInfo(buffer, _("relation %s"),
							 relname);
			break;
	}

	ReleaseSysCache(relTup);
}