kdb+

xasc data on disk (compressed)

Posted by pcarroll on March 9, 2022 at 12:00 am

From a question on topicbox:
Sorting data on disk as per code.kx.com, even when compressed

q).z.zd:17 2 6 
q)tab:flip {`dt`tm`sym`ap`bp!(x?.z.d+til 10;x?08:00+01:00*til 8;x?4?`4;x?5.0;x?5.0)}10000 
q)`:db/tab/ set .Q.en[`:db]tab `:db/tab/ 
q)meta get `:db/tab/ 
c | t f a 
---| ----- 
dt | d 
tm | u 
sym| s 
ap | f 
bp | f 
q)`tm xasc `:db/tab/ `:db/tab/ 
q)meta get `:db/tab/ 
c | t f a 
---| ----- 
dt | d 
tm | u s 
sym| s 
ap | f 
bp | f 
q)-21!`:db/tab/dt 
compressedLength | 6611 
uncompressedLength| 40016 
algorithm | 2i 
logicalBlockSize | 17i 
zipLevel | 6i

pcarroll replied 9 months, 1 week ago 2 Members · 1 Reply

1 Reply

leahs

Member
March 10, 2022 at 12:00 am

Thanks for highlighting @PCarroll, code.kx provides great references!

Happy Coding,

Leah

KX Community

xasc data on disk (compressed)

leahs