多选题Which two statements about sequences are true?()AYou use a NEXTVAL pseudo column to look at the next possible value that would be generated from a sequence, without actually retrieving the value.BYou use a CURRVAL pseudo column to look at the current value just generated from a sequence, without affecting the further values to be generated from the sequence.CYou use a NEXTVAL pseudo column to obtain the next possible value from a sequence by actually retrieving the value from the sequence.DYou use a CURRVAL pseudo column to generate a value from a sequence that would be used for a specified database column.EIf a sequence starting from a value 100 and incremented by 1 is used by more then one application, then all of these applications could have a value of 105 assigned to their column whose value is being generated by the sequence.FYou use REUSE clause when creating a sequence to restart the sequence once it generates the maximum value defined for the sequence.

多选题
Which two statements about sequences are true?()
A

You use a NEXTVAL pseudo column to look at the next possible value that would be generated from a sequence, without actually retrieving the value.

B

You use a CURRVAL pseudo column to look at the current value just generated from a sequence, without affecting the further values to be generated from the sequence.

C

You use a NEXTVAL pseudo column to obtain the next possible value from a sequence by actually retrieving the value from the sequence.

D

You use a CURRVAL pseudo column to generate a value from a sequence that would be used for a specified database column.

E

If a sequence starting from a value 100 and incremented by 1 is used by more then one application, then all of these applications could have a value of 105 assigned to their column whose value is being generated by the sequence.

F

You use REUSE clause when creating a sequence to restart the sequence once it generates the maximum value defined for the sequence.


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