Re: [Pytables-users] Table.where and conditions across tables

[Francesc A. <fa...@py...>]

On 3/27/12 2:20 AM, Alvaro Tejero Cantero wrote:
>>> (but how to grow it in columns without deleting&    recreating?)
>> You can't (at least on cheap way).  Maybe you may want to create
>> additional tables and grouping them in terms of the columns you are
>> going to need for your queries.
> Sorry, it is not clear to me: create new tables and (grouping =
> grouping in HDF5 Groups) them  in terms of the columns?
> As far as I understood, only columns in the same table (regardless the
> group of the table) can be queried together with the in-kernel engine?

Yes, but the idea is to get rid of this limitation for querying columns 
in the same table (which is somewhat artificial).  In fact, now that I 
think about this, you can actually implement queries on different 
unidimensional arrays (think of them as independent columns) by using 
the `tables.Expr` class.  More on this later.

-- 
Francesc Alted