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    <p>Assume a table called Colors with fields <code>ID</code>, <code>Color</code>, and <code>ColorIndex</code> of types <code>int</code>, <code>varchar</code>, and <code>int</code> respectively. I also assume the OP means prev / after based on an ordering of the <code>ID</code> field in <code>asc</code> order.</p> <p>You could do this without a cursor, and use a while loop...but it definately isn't set based:</p> <pre><code>DECLARE @MyID int DECLARE @CurrentIndex int DECLARE @CurrentColor varchar(50) DECLARE @PreviousColor varchar(50) SET @CurrentIndex = (SELECT 0) SET @MyID = (SELECT TOP 1 ID FROM Colors ORDER BY ID ASC) SET @CurrentColor = (SELECT '') SET @PreviousColor = (SELECT Color FROM Colors WHERE ID = @MyID) WHILE (@MyID IS NOT NULL) BEGIN IF (@CurrentColor &lt;&gt; @PreviousColor) BEGIN SET @PreviousColor = (SELECT Color FROM Colors WHERE ID = @MyID) SET @CurrentIndex = (SELECT @CurrentIndex + 1) UPDATE Colors SET ColorIndex = @CurrentIndex WHERE ID = @MyID END ELSE BEGIN UPDATE Colors SET ColorIndex = @CurrentIndex WHERE ID = @MyID SET @PreviousColor = (SELECT Color FROM Colors WHERE ID = @MyID) END SET @MyID = (SELECT TOP 1 ID FROM Colors WHERE ID &gt; @MyID ORDER BY ID ASC) SET @CurrentColor = (SELECT Color FROM Colors WHERE ID = @MyID) END </code></pre> <p>The result after execution:</p> <p><img src="https://i.stack.imgur.com/HTiox.png" alt="enter image description here"></p> <p>Performance wasn't too shabby as long as ID and color are indexed. The plus side is it is a bit faster then using a regular old CURSOR and it's not as evil. Solution supports SQL 2000, 2005, and 2008 (being that you are using SQL 2000 which did not support CTEs).</p>
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    1. POSQL Server 2000 : generating and incrementing data from column conditionally without using CURSOR
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    1. POSQL Server 2000 : generating and incrementing data from column conditionally without using CURSOR
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    1. CONot guaranteed to work - `(SELECT TOP 1 ID FROM Colors WHERE ID > @MyID)` could select the last row during the first iteration, because you don't have an `ORDER BY` clause.
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    2. CODamien - look at the top of my answer `SET @MyID = (SELECT TOP 1 ID FROM Colors ORDER BY ID ASC)` this will get the smallest value first, and being that it is integer, then the comparison operators, in this case `>`, are guaranteed to return the next value, so it is guaranteed to work.
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    3. COwithin your loop, when you try to move to the *next* `ID` value, you're *not* using an `ORDER BY` - so at the end of the first iteration, it could assign `@MyID` the highest `ID` value in the table, and skip all of the intervening rows.
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