coding style - SQL - Select null as FIELDNAME? -


i have come across code says

select null unitcost, null markup

what doing? getting field names unitcost , markup?

why use "select null as..."?

new sorry.

thanks.

that code aliasing value null , calling unitcost/markup. not selecting column available table.

you see when statement requires matching column sets, e.g. union all.

select id, col1, col2, null unitcost, null markup table_1 union select id, null col1, null col2, unitcode, markup table_2

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