I have this table below:
ID name Last
0 Joe Doe
1 Hut Nob
2 Lis Hug
3 Edy mur
I use this query to select an ID:
SELECT name FROM myDatabase WHERE ID = 2
In this case the query returns me the string Lis, now, How I can select the predecessor value?
Simple, the predecessor from 2 is 1, so I need only to do WHERE ID < 2 or WHERE ID = 2 - 1.
But this method have a problem! Lets suppose that I delete that row (ID = 1), the query will return null, because that ID not exists.
So, in this example, how I can select the predecessor from ID 2 and return ID 0? (ID 1 is gone)
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