Question

I want to specify a specific file or file group for saving a specific table in a database. how can i do this?

Answer 1

You need to be more specific. You can determine the data files that are available in a database by saying:

SELECT name, physical_name, state_desc, size, max_size, is_read_only
  FROM databasename.sys.database_files  
  WHERE type_desc = 'ROWS';

And you can see the filegroups here:

SELECT name, type_desc, is_read_only 
  FROM sys.filegroups;

But how you qualitatively pick one for creating as the destination for a new table? <shrug> – depends on how you want to decide, which we don’t know. You can determine a little more qualitative information using this join:

SELECT FileGroupName = fg.name, FileGroupType = fg.type_desc, 
    FileGroupReadOnly = fg.is_read_only, 
    [FileName] = f.name, [FileLocation] = f.physical_name, 
    [FileState] = f.state_desc, f.size, f.max_size, 
    FileReadOnly = f.is_read_only
FROM sys.filegroups AS fg
LEFT OUTER JOIN sys.database_files AS f
ON fg.data_space_id = f.data_space_id
ORDER BY fg.data_space_id;

Which will show you the files in each filegroup, their state/location/size and will show when you have unused filegroups as well (all the file columns will be NULL for those rows). So these details may help you determine which filegroup to specify.

When you’ve decided which filegroup to use, you can say:

CREATE TABLE dbo.foo(...) ON FileGroupName;

You can see the full syntax for CREATE TABLE here. You didn’t specify the version so you may have to pick the appropriate selection from the “Other versions” drop-down.