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    <p>Internally, SQL Server treats an inline table valued function much like it would a view and treats a multi-statement table valued function similar to how it would a stored procedure.</p> <p>When an inline table-valued function is used as part of an outer query, the query processor expands the UDF definition and generates an execution plan that accesses the underlying objects, using the indexes on these objects.</p> <p>For a multi-statement table valued function, an execution plan is created for the function itself and stored in the execution plan cache (once the function has been executed the first time). If multi-statement table valued functions are used as part of larger queries then the optimiser does not know what the function returns, and so makes some standard assumptions - in effect it assumes that the function will return a single row, and that the returns of the function will be accessed by using a table scan against a table with a single row.</p> <p>Where multi-statement table valued functions can perform poorly is when they return a large number of rows and are joined against in outer queries. The performance issues are primarily down to the fact that the optimiser will produce a plan assuming that a single row is returned, which will not necessarily be the most appropriate plan.</p> <p>As a general rule of thumb we have found that where possible inline table valued functions should be used in preference to multi-statement ones (when the UDF will be used as part of an outer query) due to these potential performance issues.</p>
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    1. POMulti-statement Table Valued Function vs Inline Table Valued Function
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    1. USPaul McLoughlin
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    1. COAlthough it may treat multi-statement table valued functions similar to a stored procedure, a functionally identical stored procedure is a lot faster than a table valued function for large datasets. I'm sticking with stored procs over multi-statement table valued functions.
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    2. COUnless you need to join those results in another query.
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      1. USGuillermo Gutiérrez
 

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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

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