单选题Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）AMQTBTriggerCRead Only CursorDStored Procedure
单选题
Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）
A
MQT
B
Trigger
C
Read Only Cursor
D
Stored Procedure
参考解析
解析：
暂无解析
相关考题：
View the Exhibit for some of the parameter settings. You start a session and issue the following command:SQLCREATE INDEX emp_ename ON emp(ename) TABLESPACE users INVISIBLE;What is the outcome of the above command?（）A. The index is not used by the optimizer but is maintained during DML operations.B. The index is not used by the optimizer and is not maintained during DML operations.C. The index is used by the optimizer only if a hint is specified in the query statement and is maintained during DML operations.D. The index is used by the optimizer only if a hint is specified in the query statement but is not maintained during DML operations.
A query is used to search through the database to locate a particular record or records, which conform. to specified (75) .A．criteriaB．standardsC．methodsD．conditions
Which statement is TRUE concerning buoyant work vests aboard tankers ________．A.They may be worn while working on deck but not while working over the sideB.They must be used only under supervision of a designated ship's officerC.They will be accepted for up to 10% of the required life preserversD.They may be worn during drills
Which statements concerning the value of a member variable are true， when no explicit assignments have been made？（） A、The value of an int is undetermined.B、The value of all numeric types is zero.C、The compiler may issue an error if the variable is used before it is initialized.D、The value of a String variable is "" （empty string）.E、The value of all object variables is null.
Which of the following statements best describes Flashback Versions Query？（） A、 Flashback Versions Query is used to make changes to multiple versions of data that existed between two points in time.B、 Flashback 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.C、 Flashback Versions Query is used to view version changes and the SQL to undo those changes on rows that existed between two points in time.D、 Flashback Versions Query is used to view all version changes on rows that existed between two points in time.
Which of the following statements is true regarding the VERSIONS BETWEEN clause？（） A、 The VERSIONS BETWEEN clause may be used in DML statements.B、 The VERSIONS BETWEEN clause may be used in DDL statements.C、 The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.D、 The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.
Which command can be used to display information from the PvDv object class in the ODM？（） A、odmlistB、odmshowC、lsdev -PD、lsattr -El
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.
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 thecollectors 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？（）ADuring a query’s parse time only. BDuring a query’s execution time only. CDuring any kind of DML statement execution. DDuring the execution of an INSERT statement only.
单选题Which of the following statements best describes Flashback Versions Query？（）A Flashback Versions Query is used to make changes to multiple versions of data that existed between two points in time.B Flashback 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.C Flashback Versions Query is used to view version changes and the SQL to undo those changes on rows that existed between two points in time.D Flashback Versions Query is used to view all version changes on rows that existed between two points in time.
单选题The operation of which aids to navigation may be suspended during war or national emergency（）.ANavigational satellitesBLoranCOmegaDAny of the above
多选题Which the two are true about the JSTL core iteration custom tags？（）AIt may iterate over arrays， collections， maps and strings.BThe body of the tag may contain EL code， but not scripting code.CWhen looping over collections， a loop status object may be used in the tag body.DIt may iterate over a map， but only the key of the mapping may be used in the tag body.EWhen looping over integers （for example begin1=’1’ end=’10’）， a loop status object may not be used in the tag body.
单选题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.（）AThe optimizer used a dynamic plan for the query.BThe optimizer chose different plans because automatic dynamic sampling was enabled.CThe optimizer used re-optimization cardinality feedback for the query.DThe optimizer chose different plan because extended statistics were created for the columns used.
多选题Which three functions are performed by the SQL Tuning Advisor？（）ABuilding the SQL profileBRecommending optimization of materialized viewsCChecking query objects for missing and stale statisticsDRecommending bitmap， function-based， and B-tree indexesERecommending restructuring SQL queries that are using bad plans
单选题You have many users complaining about slow inserts into a large table. While investigating the reason， you find that the number of indexes on the table is high. You want to find out which indexes are not being used. Which method would you follow to achieve this？（）Aenable index monitoring and query the DBA_OBJECTS viewBenable index monitoring and query the DBA_INDEXES viewCenable index monitoring and query the V$OBJECT_USAGE viewDenable index monitoring and view the DBA_INDEXTYPE_COMMENTS view
单选题Which is an example of a dynamic SELECT statement? （）AA query whose object names change during its execution. BA query whose object names are not known until run time. CA query whose bind variables values change during execution. DA query whose bind variable values are not known until run time.
单选题Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）AMQTBTriggerCRead Only CursorDStored Procedure
单选题Which statement is true about the database and database-user used during installation of IMS Server？（）AA preexisting database user may be used but a new database has to be created during installation.BA preexisting database may be used but a new database user has to be created during installation.CA preexisting database and user may be used or a new database and user are created during installation.DA preexisting database and user cannot be used； a new database and user are created during installation.
单选题Which of the following statements is true regarding the VERSIONS BETWEEN clause？（）A The VERSIONS BETWEEN clause may be used in DML statements.B The VERSIONS BETWEEN clause may be used in DDL statements.C The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.D The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.
多选题Which two statements are true about WHERE and HAVING clauses? （）AA WHERE clause can be used to restrict both rows and groups.BA WHERE clause can be used to restrict rows only.CA HAVING clause can be used to restrict both rows and groups.DA HAVING clause can be used to restrict groups only.EA WHERE clause CANNOT be used in a query of the query uses a HAVING clause.FA HAVING clause CANNOT be used in subqueries.
单选题When the engine room is put in standby condition, the engineer in charge of the watch need not to（）Aensure all machinery which may be used during maneuvering is in readyBensure an adequate reserve of power is available for steering gear and other requirementsCkeep the main propulsion unit controls continuously attended when in the manual mode of operationDensure all machinery which may be used during maneuvering is running stably
单选题You find this query being used in your Oracle 12c database: Which method a used by the optimizer to limit the rows being returned?（）AA filter is added to the table query dynamically using ROWNUM to limit the rows to 20 percent of the total rowsBAll the rows are returned to the client or middle tier but only the first 20 percent are returned to the screen or the application.CA view is created during execution and a filter on the view limits the rows to 20 percent of the total rows.DA TOP-N query is created to limit the rows to 20 percent of the total rows
多选题Examine the parameters for your database instance: Which three statements are true about the process of automatic optimization by using cardinality feedback?（）AThe optimizer automatically changes a plan during subsequent execution of a SQL statement if there is a huge difference in optimizer estimates and execution statistics.BThe optimizer can re optimize a query only once using cardinality feedback.CThe optimizer enables monitoring for cardinality feedback after the first execution of a query.DThe optimizer does not monitor cardinality feedback if dynamic sampling and multicolumn statistics are enabled.EAfter the optimizer identifies a query as a re-optimization candidate, statistics collected by thecollectors are submitted to the optimizer.