Configuring VNCR for Oracle RAC

By default on an Oracle RAC installation, the listeners are configured to allow any database to register with them.  There is no security out of the box to determine which databases may register.  While this makes it easy to create new databases without worrying about listener registration, this can cause potential problems in a real environment.

This can be dangerous working with RAC environments where the database registers with both a local and remote listener.  The (more...)

Oracle Apex 5.0 and APEX_JSON

How many lines of code does it take to make a web service call? Answer: 39

That is how many lines of PL/SQL I had to write in Oracle Apex 5.0 to make a web service call to an external API.

I used Adzuna's REST API to retrieve the latitude and longitude and the price of 2 bed properties for rent in a specific location in UK. The API returns JSON which the APEX_JSON (more...)

Restoring a Database to a New Diskgroup

I had the pleasure of rebuilding an Exadata rack for a customer a while back, and it provided a pretty good refresher in backup and recovery for me.  As DBAs, we back up databases all the time, but the restores are performed much less frequently.  In the case of this rack, there were several databases across multiple ASM diskgroups.  One of the goals of the rebuild was to consolidate all of the databases into a (more...)

Query existing HBase tables with SQL using Apache Phoenix

Spending a bit more time with Apache Phoenix and reading again my previous post I realised that you can use it to query existing HBase tables. That is NOT tables created using Apache Phoenix, but HBase - the columnar NoSQL database in Hadoop.

I think this is cool as it gives you the ability to use SQL on an HBase table.

To test this, let's say you login to HBase and you create an HBase (more...)

HAIP and Exadata

If you’ve run an exachk report, y0u may have seen the following message with regard to your databases:

Status Type Message Status On Details
FAIL Database Check Database parameter CLUSTER_INTERCONNECTS is NOT set to the recommended value db01:dbm011, db02:dbm012 View

This check is commonly seen when a database is created on Exadata without using the custom “Exadata” templates included with the database creation assistant.  These customized templates include a multitude of recommended parameter settings found in (more...)

Annonce : Oracle Database In-Memory Advisor

Oracle Database In-Memory Advisor est maintenant disponible.
Pour utiliser cet assistant, le "Database Tuning Pack" est nécessaire.

Plus d'information :
  • Page OTN
  • Note MOS 1965342.1

Complément : Tutoriels sur Oracle Public Cloud

Complément : Vidéos Oracle Public Cloud

Test MySQL on AWS quickly

Using sysbench to performance test AWS RDS MySQL hardware is an easy three step  operation. 

Sysbench creates synthetic tests and they are done on a 1 mil row 'sbtest' table that sysbench creates in the MySQL database you indicate. The test doesn't intrude with your database schema, and it doesn't use your data, so it is quite safe. The test is an OLTP test trying to simulate event operations in the database as it (more...)

Complément : Analyse de performances via AWR Warehouse

Annonce : Workshop DBaaS

Un workshop sur le sujet DBaaS, à destination des partenaires Oracle, aura lieu le 4 et 5 mars à Colombes (France)
Plus de détails :

MySQL Locking

Have you ever wondered if MySQL does Row Level Locking? Or wondered why are you getting the error:

ERROR 1205 (HY000) : Lock wait timeout exceeded; try restarting transaction

You get the error because your allocated time to hold a DML lock in a transaction exceeds the set limit. Usually the default limit to hold a DML row lock, set by innodb_lock_wait_timeout db parameter, is 50 seconds. If your transaction doesn't commit/rollback within 50 seconds (more...)

DBMS_SCHEDULER jobs running an hour late – DST/BST issues!

This week one of our developers highlighted the fact that the DBMS_SCHEDULER on one of our databases was running jobs an hour later than scheduled until just recently, when the clocks went back (26/10/2014) for British Summer Time (BST) …and now they’re running on-time again! I’d not seen this before, and at first I thought we


Patching Time

Just a quick note to point out that the October PSU was just released. The database has a few more vulnerabilities than usual (31), but they are mostly related to Java and the high CVSS score of 9 only applies to people running Oracle on windows. (On other operating systems, the highest score is 6.5.)

I did happen to glance at the announcement on the security blog, and I thought this short (more...)

Move That Datafile!

Moving datafiles has always been a pain.  There are several steps, it’s fairly easy to make a mistake and it requires the datafile to be offline.  There are also different steps depending on whether the database is in ARCHIVELOG mode or not.  In ARCHIVELOG mode, the steps are…

1)      Take the tablespace containing the datafile offline
2)      Copy/rename the datafile at the OS layer

Oracle 12c – New SYS-level Administration Privileges

For a while now, Oracle has been moving its security model toward a more differentiated set of privileges than just SYSDBA and SYSOPER.  We saw this in 11g with the SYSASM privilege.  This is in response to the growing number of DBA shops that delineate permissions at a more granular level, even among DBAs.  Rather than saying, “Here’s my DBA team, everyone has SYSDBA,” more and more IT shops are defining DBA (more...)

The OLAP Extension is now available in SQL Developer 4.0

Tightening Security with SELECT ANY DICTIONARY in Oracle 12c

Developers and users sometimes request the SELECT ANY DICTIONARY system privilege to enable them to view various data dictionary tables.  This may be fine for querying DBA_TABLES, etc, but the Oracle data dictionary contains a LOT of information.  Some of the views/tables are compromising from a security standpoint. (more...)

Data Pump 12c – Pumping Data with the LOGTIME Parameter

Since its release, Oracle Data Pump has been a worthy successor to the traditional exp/imp tools.  However, one area lacking with Data Pump has been something as simple as the ability to identify how long each step of a Data Pump job actually takes.  The log will show (more...)

Oracle 12c – Out With the Grid, In With the Cloud

So Oracle database 12c is out now.  The cloud (and hence the “c”) is hanging over us.  At least we don’t have to hear about “the grid” anymore.  New versions of Oracle are funny things – as DBAs, we’re kinda excited about the possibilities, but then reality (more...)