This enumeration sets the IDbCommand.CommandType property, which defines how the IDbCommand.CommandText property is interpreted. If you use Text (the default), the IDbCommand.CommandText is interpreted as a SQL command (e.g., a direct UPDATE, DELETE, INSERT, or SELECT command). If you use StoredProcedure , IDbCommand.CommandText is the name of the stored procedure you want to execute. Some providers support the use of the TableDirect CommandType . In this case, the IDbCommand.CommandText is interpreted as the name of a table from which rows will be retrieved (in a SELECT * FROM TableName style). You can also use a comma-delimited list of tables on which a join is performed. TableDirect isn't supported by all data providers. public enum CommandType { Text = 1 , StoredProcedure = 4 , TableDirect = 512 } Hierarchy System.Object Returned ByIDbCommand.CommandType , System.Data.OleDb.OleDbCommand.CommandType , System.Data.OracleClient.OracleCommand.CommandType , System.Data.SqlClient.SqlCommand.CommandType Passed ToIDbCommand.CommandType , System.Data.OleDb.OleDbCommand.CommandType , System.Data.OracleClient.OracleCommand.CommandType , System.Data.SqlClient.SqlCommand.CommandType |