Database management

Investigating Oracle lock issues with event 10704

By Franck Pachot . Did you ever encounter unexplained Oracle lock issues? They may be coming from unindexed foreign keys (which is worse in 11g). It’s not easy to monitor. Of course you can check Oracle locks from V$LOCKED_OBJECT, but(…)

Troubleshooting: ORA-29283 when oracle is member of a group with read/write privileges

Recently, I worked on an Oracle database migration for a customer and I faced a strange behavior when accessing a file stored on the file system of the Oracle database. The database has been migrated on a new server, and(…)

SQL Server 2014: Deleting files of a hekaton table

A recurrent question I have often heard about Hekaton objects is the following: Is an accidental deletion of the compilation files of a hekaton table on the file system irreversible and could this compromise the execution of SQL Server?(…)

Oracle 12c In-Memory option: waiting for 12.1.0.2

By Franck Pachot . Oracle has announced a big feature that should come in the next 12c patch set: the In-Memory option. It will soon be in beta version, so nothing will be published about it until it(…)

SQL Server 2014 : SELECT ALL USERS SECURABLES & DB admins

Microsoft will introduce four new security permissions in SQL Server 2014. One of them called SELECT ALL USERS SECURABLES is the subject of this post.  As explained by Microsoft SQL Server 2014 will allow a database administrator to manage(…)

Oracle Partitioned Sequences – a future new feature in 12c?

By Franck Pachot . Disclaimer: I'll talk about an undocumented feature that appeared in Oracle 12c - undocumented except if you consider that being exposed in DBA_SEQUENCES as the PARTITION_COUNT is a kind of documentation. So, as the syntax is(…)

Oracle is hanging? Don’t forget hanganalyze and systemstate!

By Franck Pachot . sqlplus / as sysdba oradebug setmypid oradebug unlimit oradebug hanganalyze 3 oradebug dump ashdumpseconds 30 oradebug dump systemstate 266 oradebug tracefile_name Your Oracle database – production DB, of course – is hanging. All users are blocked.

SQL Server 2014: Readable Secondary with In-Memory objects

In-Memory OLTP is one of the best new functionalities of SQL Server 2014 as it was the case with AlwaysOn and SQL Server 2012. In-Memory OLTP is fully integrated with AlwaysOn and also with AlwaysOn Availability Group. During my(…)

SQL Server 2014: Rebuilding Clustered Columnstore Indexes

I was surprised that you have to rebuild indexes that are stored In Memory. My previous posting “SQL Server 2014 – New Features: xVelocity memory optimized columnstore index” explains all processes connected with columnstore indexes. In this article, I(…)

Oracle 12c: Applying PSU 12.1.0.1.1 with Multitenant DB & unplug/plug

The concept of Multitenant databases, which was introduced with Oracle 12c in June 2013, allows to run several databases on a single instance. Oracle presents this feature as a good solution for Oracle patching. The reason behind it is(…)