Getting same sequence number from sequence object

In a typical relational database management system (RDBMS), a sequence object is used to generate unique, monotonically increasing sequence numbers. If you are using an RDBMS that supports sequences, such as PostgreSQL, Oracle, or SQL Server, you can get the same sequence number from a sequence object by retrieving the current value of the sequence without incrementing it.

Below, I'll provide examples using PostgreSQL and Oracle databases, as they both support sequences. The SQL syntax for getting the current value of a sequence without incrementing it might vary slightly between different database systems.

PostgreSQL: In PostgreSQL, you can use the currval function to get the current value of a sequence. The currval function can only be used after calling the nextval function on the sequence at least once in the current session.

1. First, create a sequence in PostgreSQL:

   sqlCopy code
   CREATE SEQUENCE my_sequence;
   

2. Get the current value of the sequence without incrementing it:

   sqlCopy code
   SELECT currval('my_sequence');
   

Oracle: In Oracle, you can use the CURRVAL pseudocolumn to get the current value of a sequence. Note that in Oracle, you must call the NEXTVAL pseudocolumn first in the same session to initialize the sequence.

1. First, create a sequence in Oracle:

   sqlCopy code
   CREATE SEQUENCE my_sequence;
   

2. Get the current value of the sequence without incrementing it:

   sqlCopy code
   SELECT my_sequence.CURRVAL FROM DUAL;
   

Please note that the ability to get the current value of a sequence without incrementing it is only possible in databases that support sequences. If you are using a different database system, such as MySQL, you might need to use alternative methods to achieve the same functionality. Additionally, it's essential to ensure that you are using the correct database driver and SQL syntax for your specific database system.