Identity columns and
SEQUENCE objects are similar in that both are methods you can use to generate sequential numbers. The main difference is that
Identity columns are part of the table definition, and you can only have one
Identity column per table.
SEQUENCE objects are independent database objects, and the sequence numbers generated can be used for any table or column.
You may want to consider using
SEQUENCE objects instead of
Identity columns under the following scenarios:
You need to know the sequence value before inserting into the table.
You want to share a series of sequence numbers between multiple ...