Question

I have a table in SQLite database of Android which has a column RANK. It is in a game application. If some user get a rank, then it’s rank should be inserted and the previously stored ranks should be incremented.

let RANK column has values 1 2 3 4 5 6 7 8 9 and a new user gets a RANK 3, then I have to insert the new user’s rank and increment the previous ranks. I mean 3 4 5 6 7 8 9 should be 4 5 6 7 8 9 10 and the newly created 3 RANK should be inserted.

Is there any library method to do this? or i have to define custom logic?

Please help me. If custom logic is needed, then at least give some hint.

Answer 1

Do this before inserting the new value, if 3 is the rank of the new value you’re going to insert:

UPDATE player SET rank=rank+1 WHERE rank >= 3;

Before:

1|a
2|b
3|c
4|d
5|e

After:

1|a
2|b
4|c
5|d
6|e

Then you can insert the new one:

INSERT INTO player VALUES(3, "new");

Giving the final result:

SELECT * FROM player ORDER BY rank;

1|a
2|b
3|new
4|c
5|d
6|e