How to use SEQUENCE in Apache Derby?

I'd like to use SEQUENCE support in Apache Derby 10.7. I've created the sequence with the following statement:

CREATE SEQUENCE SAMPLE_SEQ AS INT MAXVALUE 999999 CYCLE;

How can I select next/current value from the SAMPLE_SEQ? Could you please help me out with the query?

Apache Derby Doc says: Use a NEXT VALUE FOR expression

Should be something like

SELECT NEXT VALUE FOR SAMPLE_SEQ;

Use NEXT VALUE FOR as documented in the manual:

http://db.apache.org/derby/docs/10.7/ref/rrefsqljnextvaluefor.html#rrefsqljnextvaluefor

To get the current value of the sequence the following SQL should be executed:

SELECT CURRENTVALUE FROM SYS.SYSSEQUENCES WHERE SEQUENCENAME='SAMPLE_SEQ'

In the SQL command prompt, you can query the next value with this statement:

values NEXT VALUE FOR <sequence_name>

This will work as an expression embedded into an INSERT statement. E.g.:

INSERT INTO <table_name> (IDFIELD) VALUES (NEXT VALUE FOR <sequence_name>)

In case you want to fetch the 'current value' from the 'sequence':

Same in Java using JDBC:

ResultSet rs = conn.prepareStatement("values (next value for <sequence>)").executeQuery();
rs.next();
int seqValue = rs.getInt(1);

Source: Derby-user-mailing list archive

来源：https://stackoverflow.com/questions/5729063/how-to-use-sequence-in-apache-derby

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