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IColumnsRowset

This interface supplies complete information about columns in a rowset. The methods in it can be called from a rowset or a command.

When to Implement

Advanced providers implement this interface.

A service component can be used to synthesize IColumnsRowset from the simpler IColumnsInfo (with defaults and NULL values to round out the information).

IColumnsRowset is optional both on commands and on rowsets.

When to Call

Consumers use the methods in IColumnsRowset for detailed and flexible information about the columns of a rowset.

Note

For commands that expose ICommandPrepare, the methods on this interface can be called only after the command is prepared or the rowset is instantiated. If a command text is set but not prepared, any calls to methods on IColumnsRowset return DB_E_NOTPREPARED. For commands that do not expose ICommandPrepare, the methods on this interface can be called only after the command text has been set.

Method

Description

GetAvailableColumns

Returns a list of optional metadata columns that can be supplied in a column's rowset.

GetColumnsRowset

Returns a rowset containing metadata about each column in the current rowset. The rowset is known as the column metadata rowset and is read-only.

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