We just inherited a legacy Tempdb database with Multiple MDF files. Tempdb1 is the primary.
Example:
Tempdb1.MDF
Tempdb2.MDF
Tempdb3.MDF
(1) Was tempdb2.mdf and tempdb3.MDF being ignored the whole time?
(2) Or Is is true naming extensions don't matter? I can call 2 and 3, .mydat, or .datafile, etc. And they are still inferred as secondary?
(3) However, for best practice should I label 2/3 with .ndf?
Best Answer
Converting previous comment into answer - Sql Server does not care what extension you put on your secondary files, however, to make administration easier and make sense, why not follow the .ndf for all secondary files?