Database Administration & Monitoring

Converting a column from one data type to another in PostgreSQL

Last week at a customer the following question came up: We have a varchar2 column in Oracle that contains a date but actually is stored as a string. When we want to convert this column to be a real date(…)

12cR2 real-time materialized view (on query computation)

By Franck Pachot . Materialized views is a very old feature (you may remember that it was called snapshots a long time ago). It has all advantages of a view, as you can define any select statement that joins, filters,(…)

Oracle 12c – Combining Flashback Drop and Flashback Query

By William Sescu If you think that Flashback Drop feature just brings back your table, then this is only half of the story. It does much more than that. Besides undropping the table, it also brings back your constraints, your(…)

SQL Server Failover Cluster on Linux and synchronizing uids/gids across nodes

In my previous blog post, I talked about SQL Server on Linux and high availability. During my test, I used a NFS server to(…)

Oracle 12c – Issues with the HEATMAP Segment even if the heat map feature is not used

By William Sescu When I don’t need I feature, I don’t turn it on, or do not use it because it reduces the possibility to run into issues. Most of the times this is true, however, during the preparation for(…)

12cR2 DBCA can create a standby database

By Franck Pachot . Do you like DBCA to create a database from command line, with -silent -createDatabase? On a simple command line you can provision a database, with oratab, tnsnames.ora directory creation and any setting you want. And you(…)

Oracle Public Cloud: LIOPS with 4 OCPU in PaaS

By Franck Pachot . In the latest post I've run a cached SLOB workload on Oracle Cloud IaaS to measure logical reads per seconds on a system covered by 2 processor licences (so 4 OCPs). Just(…)

SQL Server AlwaysOn – Distributed availability groups, read-only with round-robin capabilities

This blog post comes from a very interesting discussion with one of my friends about the read-only capabilities of secondary replicas in the context of distributed availability groups. Initially, distributed availability groups are designed to address(…)

Oracle Public Cloud: 2 OCPU for 1 proc. license

By Franck Pachot . I've blogged recently about the Oracle Core Factor in the Clouds. And then, in order to optimize your Oracle licences, you need to choose the instance type that can run faster on(…)

Oracle 12c – RMAN list failure does not show any failure even if there is one

By William Sescu Relying to much on the RMAN Data Recovery Advisor is not always the best idea. In a lot of situations,  it tells you the right things, however, sometimes it tells you not the optimal things, and sometimes,(…)