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carfield

HI all We’ve run below query select minute, date, sums(size)/sum(size) from select sum(size) by 1 xbar time.minute, date from table where filtering We understand we actually should use “%” instead of “/” for divide, but I believe it just return somet...

carfield

Just wonder, if there any performance difference of using Local variable or Global variable in Q? Say there is a function, if there difference of performance of keep setting difference value to a global variable, or return value to the caller?

carfield

HI all, we are working on a system where some data need to publish from KDB to external system, as far as I aware, there are 2 approaches of getting that doneUsing native KDB Subscription as mentioned at http://www.timestored.com/kdb-guides/kdb-java-...

carfield

Hi allI just inherits a Q module and found out from the log that there are some println of "kdb error: type". It is not always happened and there should not be mismatched assignment after checking. Other than adding a lot of print line, is there anyw...

carfield

Thanks a lot, not sure if you have more idea about why this is difficult to interrupt?

carfield

Probably because it is time-series DB?

carfield

a simple solution is just divide it into smaller groups, like{ aj[`time;select from trade where date=x,sym=y;select from quote where date=x,sym=y } ./: dates cross syms

carfield

Thanks a lot

carfield

I just wonder, can any RDBMS do that without solving the whole dataset? I think the best they can do is collection some statistics and pick a better sorting algorithm?

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Question about query that stuck the KDB process

Local variable vs. Global variable

Question about publishing data from KDB to other system

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