多选题Which two statements regarding a SQL profile are true?（）AIt is built by Automatic Tuning Optimizer.BIt cannot be stored persistently in the data dictionary.CIt can be used by the query optimizer automatically.DIt can be created manually by using the CR

第1题：

Which two statements are true regarding the USING clause in table joins?（）

• A、It can be used to join a maximum of three tables 
• B、It can be used to restrict the number of columns used in a NATURAL join 
• C、It can be used to access data from tables through equijoins as well as nonequijoins 
• D、It can be used to join tables that have columns with the same name and compatible data types

第2题：

Which two statements about subqueries are true? （）

• A、A subquery should retrieve only one row.
• B、A subquery can retrieve zero or more rows.
• C、A subquery can be used only in SQL query statements.
• D、Subqueries CANNOT be nested by more than two levels.
• E、A subquery CANNOT be used in an SQL query statement that uses group functions.
• F、When a subquery is used with an inequality comparison operator in the outer SQL statement, the column list in the SELECT clause of the subquery should contain only one column.

第3题：

第4题：

Which two statements are true regarding subqueries? （）

• A、A subquery can retrieve zero or more rows 
• B、Only two subqueries can be placed atone level 
• C、A subquery can be used only in SQL query statements 
• D、A subquery can appear on either side of a comparison operator 
• E、There is no limit on the number of subquery levels in the WHERE clause of a SELECT statement 

第5题：

Which two statements are true regarding a PL/SQL package body？（）

• A、It cannot be created without a package specification.
• B、It cannot invoke subprograms defined in other packages.
• C、It can contain only the subprograms defined in the package specification.
• D、It can be changed and recompiled without making the package specification invalid.

第6题：

Which two statements are true regarding views?（）

• A、A subquery that defines a view cannot include the GROUP BY clause 
• B、A view that is created with the subquery having the DISTINCT keyword can be updated 
• C、A view that is created with the subquery having the pseudo column ROWNUM keyword cannot be updated 
• D、A data manipulation language (DML) operation can be performed on a view that is created with the subquery having all the NOT NULL columns of a table

第7题：

Which two statements about the SQL Management Base (SMB) are true? （）(Choose two.)

• A、It contains only SQL profiles generated by SQL Tuning Advisor.
• B、It stores plans generated by the optimizer using a stored outline.
• C、It is part of the data dictionary and stored in the SYSAUX tablespace.
• D、It is part of the data dictionary and stored in the SYSTEM tablespace.
• E、It contains the statement log, the plan history, plan baselines, and SQL profiles.

第8题：

第9题：

Which two statements regarding a SQL profile are true？（）

• A、 It is built by Automatic Tuning Optimizer.
• B、 It cannot be stored persistently in the data dictionary.
• C、 It can be used by the query optimizer automatically.
• D、 It can be created manually by using the CREATE PROFILE command.

第10题：

Which two statements about subqueries are true?（）

• A、A single row subquery can retrieve data from only one table.
• B、A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.
• C、A SQL query statement can display data from table B that is referred to in its subquery, without including table B in its own FROM clause.
• D、A single row subquery can retrieve data from more than one table.
• E、A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.
• F、A multiple-row subquery cannot be used in a condition where the LIKE operator is used for comparison.