Which two statements are true about the DUAL table?B) It can be accessed only by the SYS user.D) It can display multiple rows but only a single column.F) It can be used to display only constants or pseudo columns.(解析:dual 这个虚拟的表可以显示多行多列;任何用户都可以访问它。这道题...【阅读全文】
Which three statements are true about GLOBAL TEMPORARY TABLES?B) A GLOBAL TEMPORARY TABLE can have multiple indexesD) Data Manipulation Language (DML) on GLOBAL TEMPORARY TABLES generates no REDO.F) A tigger can be created on a GLOBAL TEMPORARY TABLE(解析:全局临时表跟普通表一样,...【阅读全文】