How to output non-null columns in SQL query?

Question

SQL Server

Good afternoon
There is a table:
id | Post |A1 |B1_1|B1_14|B1_23
----------------------------
1 |Master |null|1 |Null |Null
2 ​​| Head |1 |Null|1 |Null
How can I make sure that when "Master" is selected, only the B1_1 column (that is, the non-null column) is returned?

Answer 1

how are you doing?