Oracle Database as our consultants live it every day: installation and patching, upgrades, RMAN backup and recovery, Data Guard, RAC, performance tuning, multitenant, licensing, and engineered systems such as ODA and Exadata.
By Franck Pachot . If you decide to capture SQL Plan Baselines, you achieve plan stability by being conservative: if the optimizer comes with a new execution plan, it is loaded into the SQL Plan Management base, but not accepted. One day, you may add an index to improve some queries. Then you should check if there is any SQL…
To save resources I thought about the idea to start an Oracle database automatically when a first connection comes in. I.e. if there are many smaller databases on a server, which are not required during specific times, then we may shut them down and automatically start them when a connection comes in. The objective was that even the first connection…
On this Blog I described on how to install Oracle XE on a current Linux Mint version (19.3. Tricia when writing the Blog). After the conversion of the Oracle provided rpm to a deb installation file with the tool alien, you can install the Oracle XE software with a simple command root@clemens-TravelMate:/opt/distr# dpkg -i oracle-database-xe-18c_1.0-2_amd64.deb If the installation fails or…
On my old Laptop (Acer Travelmate with an Intel Celeron N3160 CPU) I wanted to install Oracle XE. Currently the available XE version is 18.4. My Laptop runs on Linux Mint 19.3 (Tricia). The Blog will describe the steps I had to follow (steps for Ubuntu would be similar). REMARK: The following steps were done just for fun and are…
I’ve published a while ago a twitter thead on some Oracle recovery concepts. For those who are not following twitter, I’m putting the whole thread here: 🔴⏬ Here I start a thread about some Oracle Database concepts. We will see how far it goes - all questions/comments welcome. 🔴⏬ A database (or DBMS - database management system) stores (for short and long term)…
During tests in Oracle 19c I recently experienced this: cbleile@orcl@orcl> select * from demo4 where m=103; cbleile@orcl@orcl> select * from table(dbms_xplan.display_cursor); … ————————————————————————— | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ————————————————————————— | 0 | SELECT STATEMENT | | | | 26439 (100)| | |* 1 | TABLE ACCESS FULL| DEMO4 | 1…
I have installed Oracle 19.6 on an EC2 for our Multitenant Workshop training. And of course, during the workshop we create a lot of PDBs. If you don’t have paid for the Enterprise Edition plus the Multitenant Option you can create at most 3 pluggable database. But with this option you can create up to 252 pluggable databases. Does it…
By Franck Pachot . Let’s say you have a PEOPLE table with FIRST_NAME and LAST_NAME and you want, in many places of your application, to display the full name. Usually my name will be displayed as ‘Franck Pachot’ and I can simply add a virtual column to my table, or view, as: initcap(FIRST_NAME)||’ ‘||initcap(LAST_NAME). Those are simple SQL functions. No…
Introduction Big Oracle databases (several TB) are still tough to migrate to another version on a new server. For most of them, you’ll probably use RMAN restore or Data Guard, but datapump is always a cleaner way to migrate. With datapump, you can easily migrate to a new filesystem (ASM for example), rethink your tablespace organization, reorganize all the segments,…
By Mouhamadou Diaw In Oracle 20c, we can now validate a Fast Start Failover configuration with the new command VALIDATE FAST_START FAILOVER. This command will help identifying issues in the configuration. I tested this new feature. The Fast Start Failover is configured and the observer is running fine as we can see below. 1 2 3 4 5 6 7…
By Mouhamadou Diaw As you may know, Oracle 20c is in the cloud with new features. The one I have tested is the PREPARE DATABASE FOR DATA GUARD. This command configures a database for use as a primary database in a Data Guard broker configuration. Database initialization parameters are set to recommended values. Let’s see what this command will do…
By Franck Pachot . Those parameters, SQLNET.EXPIRE_TIME in sqlnet.ora and ENABLE=BROKEN in a connection description exist for a long time but may have changed in behavior. They are both related to detecting dead TCP connections with keep-alive probes. The former from the server, and the latter from the client. The change in 12c is described in the following MOS note:…
