I have a database data file with 1 data file in the default filegroup. It is reaching to 500GB in size and I'm trying to learn about whether to increase the size of existing data file or add a new data file.
If I add a new file into the default file group, then SQL engine will use round robin/proportional fill algorithm to fill data extents into the files.
Assuming partitioning isn't used, disk space limit isn't an issue, and also IO latency is acceptable, then there is no benefit to having a separate data file because even one data file can technically be read in parallel, irrespective of whether the files are on same or separate drive.
Is this correct understanding?
