Table with only composite primary key?

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1

Content-Disposition: inlineHello,

Why does the following q statement result in a 'parse error?

q)d:([a:`int$();b:`long$();c:`symbol$()])
'parse
q)

I think with this statement I am creating a table d with 3 columns a,b&c and a composite key with all of them. There are no more columns in the table d.

Thanks,
Yuva

2

yuva,

a table with primary keys is in fact of a dictionary that maps a table over another table.

so, you are creating only the keys but no values.

if you need something like this, add a dummy column and everything should work.

btw, are you sure you need this kind of table?

felix

3

Well, this is a table in a database schema of an application[1] thatrequires it. I think (I don’t know for sure) that this is used fortable joins.Hmm…, having a dummy column only to create a join/link table looks strange.Thanks for the hint.~Yuva[1] TPC-E has a data driver called EGen. This kind of table occursthere. Is there a q equivalent for the TPC-E benchmark?On 6/26/08, Felix LUNGU <felix.lungu> wrote:> yuva,> a table with primary keys is in fact of a dictionary that maps a table over> another table.>> so, you are creating only the keys but no values.>> if you need something like this, add a dummy column and everything should> work.>> btw, are you sure you need this kind of table?>> felix>> On Fri, Jun 27, 2008 at 1:12 AM, Yuvaraj Athur Raghuvir <> yuvaraj.a.r@gmail.com> wrote:>>> Hello,>>>> Why does the following q statement result in a 'parse error?>>>> q)d:([a:`int$();b:`long$();c:`symbol$()])>> 'parse>> q)>>>> I think with this statement I am creating a table d with 3 columns a,b&c>> and a composite key with all of them. There are no more columns in the>> table>> d.>>>> Thanks,>> Yuva>>>>>> >>>>> >>– Sent from Gmail for mobile | mobile.google.com</felix.lungu>