5,2使用 SELECT语句查询数据 524 WHERE子句 WHERE search condition old outer join search condition >ii= [NOT]≤ predicate>|( searth_condition>)3 [{AND丨OR}[NoT] predicate >(< searth_condition>)31 ■■5.2 使用SELECT语句查询数据 5.2.4 WHERE子句 WHERE < search_condition > | < old_outer_join > < search_condition > ::= { [ NOT ] < predicate > | ( < searth_condition > ) } [ { AND | OR } [ NOT ] { < predicate > |( < searth_condition > ) } ] } [ ,...n ]