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Which statement is true about the database and database-user used during installation of IMS Server？（）A、A preexisting database user may be used but a new database has to be created during installation.B、A preexisting database may be used but a new database user has to be created during installation.C、A preexisting database and user may be used or a new database and user are created during installation.D、A preexisting database and user cannot be used； a new database and user are created during installation.
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Examine the parameter for your database instance: You generated the execution plan for the following query in the plan table and noticed that the nested loop join was done. After actual execution of the query, you notice that the hash join was done in the execution plan: Identify the reason why the optimizer chose different execution plans.（）A、The optimizer used a dynamic plan for the query.B、The optimizer chose different plans because automatic dynamic sampling was enabled.C、The optimizer used re-optimization cardinality feedback for the query.D、The optimizer chose different plan because extended statistics were created for the columns used.
Which two statements are true about WHERE and HAVING clauses? （）A、A WHERE clause can be used to restrict both rows and groups.B、A WHERE clause can be used to restrict rows only.C、A HAVING clause can be used to restrict both rows and groups.D、A HAVING clause can be used to restrict groups only.E、A WHERE clause CANNOT be used in a query if the query uses a HAVING clause.F、A HAVING clause CANNOT be used in subqueries.
Examine the parameters for your database instance: Which three statements are true about the process of automatic optimization by using cardinality feedback?（）A、The optimizer automatically changes a plan during subsequent execution of a SQL statement if there is a huge difference in optimizer estimates and execution statistics.B、The optimizer can re optimize a query only once using cardinality feedback.C、The optimizer enables monitoring for cardinality feedback after the first execution of a query.D、The optimizer does not monitor cardinality feedback if dynamic sampling and multicolumn statistics are enabled.E、After the optimizer identifies a query as a re-optimization candidate, statistics collected by the collectors are submitted to the optimizer.
Which is an example of a dynamic SELECT statement? （）A、A query whose object names change during its execution. B、A query whose object names are not known until run time. C、A query whose bind variables values change during execution. D、A query whose bind variable values are not known until run time.
单选题When does Oracle9i flag an index as being used in the V$OBJECT_USAGE view？（）A During a query’s parse time only. B During a query’s execution time only. C During any kind of DML statement execution. D During the execution of an INSERT statement only.
单选题Which of the following statements best describes Flashback Versions Query？（）AFlashback Versions Query is used to make changes to multiple versions of data that existed between two points in time.BFlashback Versions Query is used to view all version changes on rows that existed between the time the query was executed and a point in time in the past.CFlashback Versions Query is used to view version changes and the SQL to undo those changes on rows that existed between two points in time.DFlashback Versions Query is used to view all version changes on rows that existed between two points in time.
