Hi Jeff

I really appreciate you looking at this. Posting this makes me think more about what I'm doing, and your replies meant I had to ask the user some more meaninful questions. I've had the problem for about 3 weeks - the user is in no rush as the old file system works - but they have no Fortran support, so they want it done eventually.

Now that I've got the base level of data out of the user, I can start devising a structure

something like

CREATE TABLE Transform(

pKey int identity,

FK_SubGroupID int

FK_GroupID int,

FK_BlockID int

FK_FileID int

x float,

y float,

z float,

vx float,

vy float

vz float )

Then Tables to link to the SubGroups, Groups, Blocks and Files

... it probably needs a bit more work - and some indexes.