public SqlQueryable <T> Update(Expression <Func <T> > expression) { if (expression == null) { throw new ArgumentNullException("expression", "Value cannot be null"); } this.Clear(); this._sqlBuilder.SetSqlCommandType(SqlCommandType.Update); this._sqlBuilder.IsSingleTable = true; this._sqlBuilder.SqlUpdateStr = $"update {this._mainTableName} set "; SqlProvider.Update(expression.Body, this._sqlBuilder); return(this); }