In relation to my previous blog about custom facets not showing up after full reindex, a customer was doing a migration that just completed. After the full reindex, there were no facets because of what I explained in the blog. Knowing that the online rebuild is normally faster than a full reindex, I helped to start this operation but after…
Beginning of the year, while performing a migration from a Documentum 7.3 environment on VM to Documentum 16.4 on Kubernetes, a customer had an issue where their custom facets weren’t showing up on D2 after a full reindex. At the end of the migration, since xPlore has been upgraded as well (from xPlore 1.5 to 16.4, from VM to K8s),…
By Franck Pachot . We have an incredible number of possibilities with Oracle. Yes, an index can be global (indexing many partitions without having to be partitioned itself on the same key) and partial (skipping some of the table partitions where we don’t need indexing). In the previous post of this series of small examples on recent features I partitioned…
By Franck Pachot . In this series of small examples on recent features, I have imported in a previous post, the statistics of covid-19 per day and per countries. This is typical of data that comes as a time-series ordered by date, because this is how it is generated day after day, but where you probably want to query from…
By Franck Pachot . On Twitter, Ludovico Caldara mentioned the #licensing #pitfall when using the Online Partition Move with Basic Compression. Those two features are available in Enterprise Edition without additional option, but when used together (moving online a compressed partition) they enable the usage of Advance Compression Option: https://twitter.com/njesp/status/1251961678020960257?s=20 And there was a qustion about detection of this feature.…
By Franck Pachot . Want to test some DDL, a query, check an execution plan? You need only a browser. And you can copy-paste, or simply link, your test-case in a forum, a tweet, an e-mail, a tweet. Here is a small list (expecting to grow from your comments) of free online services which can run with an Oracle Database:…
It’s time to a new blog about partitioning improvement in 12cR2. After auto-list partitioning and multi-column list partitioning & read-only partitions, I’ll demonstrate how we can easily convert a non-partitioned table to a partitioned table…online ! As a reminder, the way to convert a table to a partitioned table were to use the DBMS_REDEFINITION package (since 9i to 12cR1) which…
By Franck Pachot . On Linux, when you move a datafile, with “mv” within the filesystem it’s just a rename. There is no copy. In 12c you can move a datafile online where oracle takes care of the move at OS level. But be careful. Even if you are in the same filesystem, moving a datafile online does a copy…
By Franck Pachot . I’ve described in previous posts how the 12c online datafile move works: your session process do the copy and tells other writers (dbwr and direct-path inserts) to write blocks to both files (old one and new one for blocks that have already been copied). Readers read old file until the copy is completed. The target file…
By Franck Pachot . Here is a long answer for a question on our forum about online move: what is internal mechanism to store/keep ongoing changes in that particular datafile while copying is in progress. The short answer is that there is absolutely no lock, just small synchronization and messaging between sessions. And a very small overhead while the move…
By Franck Pachot . Do you think that online operations are available only on Enterprise Edition? That changed in 12c, there is an operation that is online (without the need for the ONLINE keyword) and available in Standard Edition and a very important feature for performance tuning: invisible indexes. Example I’ll show it from the SCOTT schema where I’ve added…
