Triton Db2 Geek

Confessions of a DB2 geek

IBM Gold Consultant Program and IBM Premier business Partner

Category Archives: DB2 11.1

Client Experiences: How DB2 Migration Affects Decimal Type Conversion

Published February 12th, 2019 - by

Recently, I assisted a client migrating their DB2 databases from v9.7 to v11.1. I intentionally say “migrating” and not “upgrading”, even though three major releases were jumped, because the existing databases were located on Z-Linux servers (big endian) and the target databases were to be placed on POWER Linux servers (little endian), so it was Continue Reading

Finding the access path for Columnar queries #3

Published March 13th, 2018 - by

In the first blog in this series ( Finding the access path for Columnar queries ) I was griping about not being able to see any detail in the explain plans for what DB2 is doing when you see a table scan (TBSCAN) of a column-organized table. I mention that each columnar table will have Continue Reading

Finding the access path for Columnar queries #2

Published November 8th, 2017 - by

Usage Lists In my last blog ( http://db2geek.triton.co.uk/finding-access-path-columnar-queries ) I was reiterating the case for columnar data storage but bemoaning the lack of any means to see in the access path how the data is being retrieved. It merely shows as a table scan (TBSCAN) and you need to trust that what is going on Continue Reading

Finding the access path for Columnar queries

Published October 18th, 2017 - by

Columnar Data : how it works We’re probably all fairly familiar now with BLU acceleration and the advantages of storing analytical data in a columnar format. If not, and by way of a recap; what we can now do is return much smaller results sets to our analytical queries, in a highly-compressed format, thereby reducing Continue Reading

In-Line Optimization with V11.1

Published April 7th, 2017 - by

Sometimes you might find that the Optimizer has chosen an access path with which you don’t concur. It’s not that likely, as the DB2 Optimizer is one of the most sophisticated of its ilk, but it’s possible that you may know something that the optimizer doesn’t: if, for instance, a table has just had some Continue Reading

Next Page »