Hi All,
I am new to kdb and wanted to prepare a report containing information of how many rows are seen in variable rdb tables. For this I see we can get that via below functional query that provide us dictionary with table name and count
(tables[] ! { count value (? ; x ; () ; 0b ; () ) } each tables[]
Above gives me the expected output, but I wanted to perform this via qsql for my understanding. But this gives me the error.
tables[] ! ( { count value ( select from x ) } each tables [] )
I tried to use the implicit argument x and passed it to function which then count the number of rows inside the lambda function and then tried passing it parameter each tables which results into an error. How can I debug this error with some meaningful error thrown and what would be right way to do it ?
You then replace the parse tree with a qsql statement which evaluates, this means you no longer need value:
tables[]!{count select from x} each tables[]
The debugger uses ^ to show you exactly where the error is thrown
// ^ tells us the error happened when value was run
q)tables[] ! ( { count value ( select from x ) } each tables [] ) 'type [2] { count value ( select from x ) } ^
q))select from x // select from x returns a table a - 1 2 3 q))value select from x //Running value on a table is not a valid command 'type [4] value select from x ^
q))count select from x //We should run count directly on the returned table 3