请问怎么实现类似于python的解包，以达到选择name_set中所有名称的列？
例如，对于下表T，name_set为其3个列的列名，怎么查询这3列？
T=table(1..3 as id,2..4 as val1,3..5 as val2,4..6 as val3)name_set=["val1","val2","val3"]select *name_set from tmpTable
用元编程的方式可实现：
T=table(1..3 as id,2..4 as val1,3..5 as val2,4..6 as val3) name_set=["val1","val2","val3"] sql(sqlCol(name_set),T).eval()
执行后，结果为：
val1 val2 val3 2 3 4 3 4 5 4 5 6
