SQL-Calculation view

Hello ,

I am trying to read Calculation view data using SQL statement , but when I have SQL for ex as below , it says invalid col name , though the col is present in the view output .

select * from <calc view> where _ABS_TEST123_From = <some value>  ---Error message saying

_ABS_TEST123_From is not a valid col.

but when i have

select * from <calc view> where _ABS_TEST345 = <some value> , it works fine .

Code in SAP HANA Studio :

select * from"_SYS_BIC"."<Calc view name >"  where _MAT0331_FrVaEx = 'X' --Here _MAT0331_FrVaEx col is available in calc view output .but it gives error message Invalid col name

Please advise .

Thanks

Shishupal