单项选择题X 纠错
A.It ignores NULL values
B.Reversing the order of the intersected tables alters the result
C.The names of columns in all SELECT statements must be identical
D.The number of columns and data types must be identical for all SELECT statements in the query
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单项选择题
A.CREATE SYNONYM ord FOR orders; This command is issued by OE
B.CREATE PUBLIC SYNONYM ord FOR orders; This command is issued by OE
C.CREATE SYNONYM ord FOR oe.orders; This command is issued by the database administrator
D.CREATE PUBLIC SYNONYM ord FOR oe.orders; This command is issued by the database administrator
多项选择题
A.when a DELETE statement is executed
B.when a ROLLBACK command is executed
C.when a PL/SQL anonymous block is executed
D.when a data definition language (DDL) statement is executed
E.when a TRUNCATE statement is executed after the pending transact ion
单项选择题
A.It can have a maximum of five expressions in a list
B.It returns the highest NOT NULL value in the list for all rows
C.It requires that all expressions in the list must be of the same data type
D.It requires that at least one of the expressions in the list must have a NOT NULL value
单项选择题
A.RMAN will attempt to make the backup run as fast as possible without any IO limitations.
B.RMAN will automatically restrict the number of channels in use to one.
C.RMAN will spread the backup IO over the total duration stated in the backup command.
D.RMAN will skip any datafile that currently is involved in an IO operation. RMAN will retry backing up the datafile later and an error will be raised at the end of the backup if the datafile cannot be backed up.
E.Datafiles will be backed up; those having the lowest current number of IO operations will be backed up first.
单项选择题
A.V$SESSION_EVENT
B.V$SESSION
C.V$W0041ITS
D.V$WAITSTAT
E.V$SESSION_LONGOPS
单项选择题
A.The backup set has exceeded the retention criteria set in RMAN and is eligible for removal.
B.The backup set has one or more invalid blocks in it and is not usable for recovery.
C.The backup set contains one or more tablespaces no longer in the database.
D.The backup set contains one or more missing backup set pieces.
E.The backup set is from a previous version of RMAN and was not upgraded.
单项选择题
A.backup database plus archivelog
B.backup database plus archivlog until time ‘10:00‘
C.backup database plus archivelog timeout ‘10:00‘
D.backup database plus archivelog duration 10:00
单项选择题
A.synch catalog
B.resync catalog
C.replicate catalog
D.update catalog
E.restore catalog
单项选择题
A.list database backup
B.report database backup
C.list backup of database
D.list summary backup
E.report backup of database
单项选择题
A.Database Datafiles
B.Database Control Files
C.Online redo logs
D.Archived redo logs
E.The database SPFILE
F.None of the above, all these files are backed up.