Strange column names in execution plan

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Strange column names in execution plan

curious_sqldba

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November 6, 2013 at 4:09 pm

#278913

In the attached execution plan, at the sort operator(50% cost),when i hover over the operator in the plan i see something like "Expr 1088" ascending, why does it show like that?

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Keith Tate SSCrazy Eights Points: 9938 More actions · Answer 1

That is simply the name of the output (one of them) from the Compute Scalar operation right before the sort. Also, you have some carnality issues with this query (not sure if this is a real query or not), but the estimated rows and the actual rows are way off in some instances.

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Sean Pearce SSCoach Points: 15999 More actions · Answer 2

These are internal expressions produced when SQL Server executes the query.

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curious_sqldba SSC-Dedicated Points: 36494 More actions · Answer 3

Keith Tate (11/6/2013)
That is simply the name of the output (one of them) from the Compute Scalar operation right before the sort. Also, you have some carnality issues with this query (not sure if this is a real query or not), but the estimated rows and the actual rows are way off in some instances.

But then why is it showing a column name for the other one?

Sean Pearce SSCoach Points: 15999 More actions · Answer 4

curious_sqldba (11/7/2013)
Keith Tate (11/6/2013)
That is simply the name of the output (one of them) from the Compute Scalar operation right before the sort. Also, you have some carnality issues with this query (not sure if this is a real query or not), but the estimated rows and the actual rows are way off in some instances.
But then why is it showing a column name for the other one?

The scalar operator immediately before the sort is calculating the value of [Expr1088]. Included in the output of the scalar operator is the new expression [Expr1088] and the column [Column7]. The sort operator is then sorting on [Expr1088] and [Column7].

In other words, [Expr1088] is a calculated value while [Column7] is a value from your table.

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