On Sat, 4 Apr 2009, Xiao Yafeng wrote:
3. Could I define primary key for a bag variable?
All items in a Bag are "primary keys", but there's no data additional
data associated with it.
I mean whether I can see Set as a table and Bag as a table with a
unique constraint? like:
subset test of Bag(test_name Str, test_ID Int, primary key(test_ID))
I don't think you can really do something like that. Perl 6 as
specified leaves many things up to libraries. Implementing a Table type will
no doubt be one of those things. I would like to have a Table type that will
work well with the Tree/Plex type that I am working on.
In the meantime, a table would need to be represented as an array of
hashes, or a hash of arrays.
HTH,
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| Name: Tim Nelson | Because the Creator is, |
| E-mail: wayl...@wayland.id.au | I am |
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