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Getting SQL Server Column Metadata Without Returning Data

Getting SQL Server Column Metadata Without Returning Data Problem You need to retrieve the column metadata from a SQL Server command or stored procedure without returning any data. | Team LiB Recipe 10.12 Getting SQL Server Column Metadata Without Returning Data Problem You need to retrieve the column metadata from a SQL Server command or stored procedure without returning any data. Solution Use the SET FMTONLY ON statement. The sample code creates and executes a query statement to retrieve only column metadata from the Orders table in the Northwind sample database. A new DataTable is created from this information. The C code is shown in Example 10-12. Example 10-12. File ColumnSchemaSPForm.cs Namespaces variables and constants using System using System.Configuration using System.Data using System.Data.SqlClient . . . Create the SQL statement to retrieve only the column schema. String cmdText SET FMTONLY ON SELECT FROM Orders SET FMTONLY OFF Use a DataAdapter to fill the DataTable. SqlConnection conn new SqlConnection ConfigurationSettings.AppSettings Sql_ConnectString SqlCommand cmd new SqlCommand cmdText conn SqlDataAdapter da new SqlDataAdapter cmd DataTable dt new DataTable da.Fill dt Bind the default view of the table to the grid. dataGrid.DataSource dt.DefaultView Discussion Recipe 10.9 discusses the SQL SET statement. When SET FMTONLY is ON no rows are processed or sent to a client when a SQL statement or stored procedure is executed only metadata is returned to the client. The DataTable created is identical to one that would have been created if the SQL command used a WHERE clause that returned an empty result set. For more information about the SET FMTONLY statement see the topic SET in Microsoft SQL Server Books Online. Team LiB