kdb+ and q
Q+A on all things kdb+ database and the q language
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Resolved! merge/copy partitioned tables efficiency

Hello all, Currently, I would need to merge/copy partitioned tables from several individual folders to a common large folder: kdbfolder_1 - - trade - col_1,...,col_n ...kdbfolder_n - - trade - col_1,...,col_n--> kdbcommon - - trade - col_1,...,col...

jackyyuk by New Contributor
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Resolved! Interaction between peach and other optimisations

I understand there are various parallel optimisations that happen under the hood when running with some number of secondary threads, e.g. summing across multiple partitions. How do these interact with peach? For example: disk0/hdb/par.txt --> disk1/h...

erichards by New Contributor II
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Reloading HDB causes "Cannot allocate memory" error

Hi, we are running an HDB instance that loads from a partitioned database on the disk. To reload the indexing of the HDB after updating the database, we run the following: \l . This was working in the past but recently it has been running into the er...

clivelo by New Contributor II
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Resolved! Web interface, JSON

Hi - does anyone have a customization to the .z.ph handler that would allow the caller to receive JSON data, the same way that adding q.csv to the URL would result in a CSV file being returned from the server? TIA

grigora by New Contributor II
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Resolved! Performance using a table to combine where phrases

Hi all, Passing a table in to a where clause instead of the individual values significantly affects performance, even compared to using & to join all the where phrases into one. What is the query doing under the covers? 1#.eoh.f date SRC PRICE_TYPE I...

eohara_kdb by New Contributor III
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  • 2 replies
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