SQL TIP: Auto Increment in an UPDATE statement.
I needed to create a temp table in SQL with a column that contained an incrementing integer, without making that column an identity.
For example, suppose I want to select record from a table of users, but add a column that contains an incrementing counter. The data in the table should look like so:
To start, I can run the following query to create the temp table:
SELECT counter = 0, * FROM Users INTO #tmp_Users
This creates a temp table named
#tmp_Users where the column “counter”
is set to 0 for each row.
In order to update the counter column so that each row has a counter value greater than the previous row, run the following statement.
DECLARE @counter int SET @counter = 0 UPDATE #tmp_Users SET @counter = counter = @counter + 1
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