Create a SQLite view where a row depends on the previous row

Question

I\'d like to create a view in SQLite where a field in one row depends on the value of a field in the previous row. I could do this in Oracle using the LAG analy

Answer 1

Assuming that you don't delete this will work:

SELECT t2.DAY, t2.price, t2.price-t1.price 
FROM TABLENAME t1, TABLENAME t2 
WHERE t1.rowid=t2.rowid-1

This works because every row has its own rowid even if you dont specify it in the CREATE statement.

If you do delete, it becomes:

SELECT t2.day, t2.price, t2.price-t1.price 
FROM 
     (SELECT l1.day, l1.price, 
          (SELECT COUNT(*) 
          FROM TABLENAME l2 
          WHERE l2.rowid < l1.rowid) AS count
      FROM TABLENAME l1) AS t1,
     (SELECT l1.day, l1.price, 
          (SELECT COUNT(*) 
          FROM TABLENAME l2 
          WHERE l2.rowid < l1.rowid) AS count
      FROM TABLENAME l1) AS t2
WHERE t1.count=t2.count-1

This works under the assumption that rowids are always increasing.