How Can I Get the Current Oracle Sequence Value Without Incrementing It?

Retrieving Oracle Sequence Value Without Incrementing

Retrieving the current value of an Oracle sequence without incrementing it can be achieved through the SELECT statement with the last_number column from relevant database views.

To retrieve the sequence value, follow these steps:

1. Identify the sequence owner and name.
2. Execute the following query, replacing and accordingly:

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

3. Alternatively, if the sequence is in your default schema, you can use user_sequences:

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

Note: The user_sequences, all_sequences, and dba_sequences views provide various sequence metadata.

Advanced Technique (Not Recommended):

While not recommended, it's possible to do this more reliably by using a series of operations:

1. Retrieve the sequence increment value:

SELECT increment_by I
FROM user_sequences
WHERE sequence_name = 'SEQ';

2. Retrieve the sequence value:

SELECT seq.nextval S
FROM dual;

3. Alter the sequence to decrement by the increment value:

ALTER SEQUENCE seq
INCREMENT BY -1;

4. Retrieve the sequence value again (decremented):

SELECT seq.nextval S
FROM dual;

5. Reset the sequence to its original increment:

ALTER SEQUENCE seq
INCREMENT BY 1;

Caution: This technique may cause issues if multiple users are accessing the sequence concurrently.

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