Short answer: meta tablename
For example –
q)\l sp.q / found in $QHOME/sp.q q)s s | name status city --| ------------------- s1| smith 20 london s2| jones 10 paris s3| blake 30 paris s4| clark 20 london s5| adams 30 athens q)meta s c | t f a ------| ----- s | s name | s status| i city | s q)
The output of meta is a kdb table, where columns c and t indicate the column name and data type, respectively.
The key the provides an alternate method:
q)key exec city from s `symbol q)
If you need the type code, use the type function:
q)type exec city from s 11h q)
See also: Type character definitions, Meta output faq.