Click here to monitor SSC
SQLServerCentral is supported by Red Gate Software Ltd.
 
Log in  ::  Register  ::  Not logged in
 
 
 
        
Home       Members    Calendar    Who's On


Add to briefcase

Need clarity on Page Compression Expand / Collapse
Author
Message
Posted Wednesday, July 16, 2008 5:29 PM
SSC-Addicted

SSC-AddictedSSC-AddictedSSC-AddictedSSC-AddictedSSC-AddictedSSC-AddictedSSC-AddictedSSC-Addicted

Group: General Forum Members
Last Login: Today @ 10:40 AM
Points: 418, Visits: 788
Hi Gurus,

Few queries on the Prefix compression logic. As per PrefixComp2 pic, "In the first column of the first row, the value 4b indicates that the first four characters of the prefix (aaab) are present for that row, and also the character b. This makes the resultant value aaabb, which is the original value." This I could understand based on PrefixComp1 and PrefixComp2 images.

But in Dictionary compression, 4b is being referred by Col1 and Col2 values, but as per image 1 the col1 & 2 values are aaabb (4b=first 4 ltrs(ie aaab) + b) & aaaab (4b=first 4 ltrs(ie aaaa) + b) so the first 4 ltrs are different in the columns but how it can refer 4b (CI) for col1 and Col2 ?

I'm not sure I misunderstood or ??? ... Kindly clarify.

Have a good day...

Warmest
Jay.



Thanks
Jay
http://www.sqldbops.com


  Post Attachments 
PrefixComp1.gif (9 views, 2.96 KB)
PrefixComp2.gif (7 views, 6.61 KB)
PrefixComp3.gif (5 views, 4.92 KB)
Post #535618
« Prev Topic | Next Topic »

Add to briefcase

Permissions Expand / Collapse