How Can I Retrieve the Current Value of an Oracle Sequence Without Incrementing It?

Retrieving Sequence Value Without Incrementing

Oracle sequences provide a convenient way to generate incrementing values for use in database applications. However, sometimes it may be desirable to retrieve the current value of a sequence without incrementing it.

One method involves using the last_number column from the all_sequences view:

SELECT last_number
FROM all_sequences
WHERE sequence_owner = '<sequence owner>'
AND sequence_name = '<sequence_name>';

This query returns the last value generated by the sequence without incrementing it.

For sequences in the default schema, you can use the user_sequences view instead:

SELECT last_number
FROM user_sequences
WHERE sequence_name = '<sequence_name>';

Another approach, which avoids the need for a separate query, is to increment and decrement the sequence value:

SELECT seq.nextval AS next_value
FROM dual;

-- Decrement the sequence by the same amount it was incremented
ALTER SEQUENCE seq INCREMENT BY -1;

SELECT seq.nextval AS next_value
FROM dual;

-- Reset the sequence to its original increment
ALTER SEQUENCE seq INCREMENT BY 1;

However, it's important to note that this method may not be reliable if other sessions are concurrently using the sequence, as it could lead to Oracle sequence errors.

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