1Z0-042報(bào)關(guān)編碼每日一練(2020.03.29)

A.The database files are synchronized.
B.Uncommitted changes are not rolled back.
C.The database is closed， but the instance is still started.
D.Database buffers and redo buffers are not written to the disk.
E.The database undergoes automatic media recovery during the next startup.

A.It degrades the run time and compiler performance.
B.It provides better run time and compiler performance.
C.It provides better optimization of the statement during parse time.
D.It forces the rule based optimizer to be used for statement optimization.
E.It provides better run time performance but slightly degraded compiler performance. 
F.It provides better run time performance but slightly degraded run time performance.

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.

A.Upgrade the hardware/memory to accommodate the data.
B.Load the data into your database by using the PARALLEL clause.
C.Give analysts DBA privilege， so that they can query DBA_EXTERNAL_TABLES.
D.Use an external table so you can have the metadata available in your database， but leave the data in the operating system files.

A.Set the UNDO_RETENTION parameter to AUTO.
B.Create an initial undo segment in undotablespace.
C.Set the UNDO_RETENTION parameter to 900 or more
D.Set the initialization parameter UNDO_MANAGEMENT to AUTO
E.Set the UNDO_MANAGEMENT parameter to the name of an undotablespace