Esempio n. 1
0
        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);
        }