多选题Which two statements are true when row archival management is enabled?（）AThe ORA_ARCHIVE_STATE column visibility is controlled by the ROW ARCHIVAL VISIBILITY session parameter.BThe ORA_ARCHIVE_STATE column is updated manually or by a program that could

第1题：

GEM机箱的地址插板从下往上依次作用是（）

• A、Row，notused，Column，MagazineAddress
• B、Row，Column，notused，MagazineAddress
• C、Column，Row，notused，MagazineAddress
• D、notused，Row，Column，MagazineAddress

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：

As a result of performance analysis， you created an index on the prod_name column of the prod_det table， which contains about ten thousand rows. Later， you updated a product name in the table. How does this change affect the index？（）

• A、A leaf will be marked as invalid.
• B、An update in a leaf row takes place.
• C、The index will be updated automatically at commit.
• D、A leaf row in the index will be deleted and inserted.
• E、The index becomes invalid when you make any updates.

第5题：

Which two are true about aggregate functions? （）

• A、You can use aggregate functions in any clause of a SELECT statement.
• B、You can use aggregate functions only in the column list of the select clause and in the WHERE clause of a SELECT statement.
• C、You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
• D、You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
• E、You can use aggregate functions on a table, only by grouping the whole table as one single group.
• F、You cannot group the rows of a table by more than one column while using aggregate functions.

第6题：

Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?（）

• A、Define the column MAINID as NOT UPDATABLE
• B、Define the column MAINID as a PRIMARY KEY
• C、Define the column MAINID as a FOREIGN KEY
• D、Define an UPDATE trigger on table TABLEX

第7题：

Which three statements about subqueries are true?（）

• A、A single row subquery can retrieve only one column and one row.
• B、A single row subquery can retrieve only one row but many columns.
• C、A multiple row subquery can retrieve multiple rows and multiple columns.
• D、A multiple row subquery can be compared by using the ">" operator.
• E、A single row subquery can use the IN operator.
• F、A multiple row subquery can use the "=" operator.

第8题：

第9题：

Which two statements are true about a bitmap index？ （）

• A、It is recommended for the columns that have unique values.
• B、It can be converted to a B-tree index by using the ALTER INDEX command.
• C、It has a bitmap segment for each distinct value in the key column， containing a string of bits in which each bit represents the presence or absence of a key column value.
• D、Updating the key column locks the whole bitmap segment that contains the bit for the key value to be updated.

第10题：

Which statement describes the effect on an index， when the indexed column for the rows is updatedin the base table（）

• A、An update in a leaf row takes place.
• B、The index becomes invalid after the update.
• C、The leaf block containing the row to be updated is marked as invalid.
• D、A row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted