private DbCommand CreateCommand(DbProviderManifest manifest, DbCommandTree commandTree) { if (manifest == null) { throw new ArgumentNullException("manifest"); } if (commandTree == null) { throw new ArgumentNullException("commandTree"); } var expectedTypes = PrepareTypeCoercions(commandTree); FbCommand command = FbCommand.CreateWithTypeCoercions(expectedTypes); List <DbParameter> parameters; CommandType commandType; command.CommandText = SqlGenerator.GenerateSql(commandTree, out parameters, out commandType); command.CommandType = commandType; // Get the function (if any) implemented by the command tree since this influences our interpretation of parameters EdmFunction function = null; if (commandTree is DbFunctionCommandTree) { function = ((DbFunctionCommandTree)commandTree).EdmFunction; } // Now make sure we populate the command's parameters from the CQT's parameters: foreach (KeyValuePair <string, TypeUsage> queryParameter in commandTree.Parameters) { FbParameter parameter; // Use the corresponding function parameter TypeUsage where available (currently, the SSDL facets and // type trump user-defined facets and type in the EntityCommand). FunctionParameter functionParameter; if (null != function && function.Parameters.TryGetValue(queryParameter.Key, false, out functionParameter)) { parameter = CreateSqlParameter(functionParameter.Name, functionParameter.TypeUsage, functionParameter.Mode, DBNull.Value); } else { parameter = CreateSqlParameter(queryParameter.Key, queryParameter.Value, ParameterMode.In, DBNull.Value); } command.Parameters.Add(parameter); } // Now add parameters added as part of SQL gen (note: this feature is only safe for DML SQL gen which // does not support user parameters, where there is no risk of name collision) if (null != parameters && 0 < parameters.Count) { if (!(commandTree is DbInsertCommandTree) && !(commandTree is DbUpdateCommandTree) && !(commandTree is DbDeleteCommandTree)) { throw new InvalidOperationException("SqlGenParametersNotPermitted"); } foreach (DbParameter parameter in parameters) { command.Parameters.Add(parameter); } } return(command); }