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Archive for the ‘Sybase’ Category

What is the best relational database?

In DB2 database, DBA, MySQL, Oracle database, PostgreSQL, SQL Server, Sybase on May 11, 2013 at 11:45

“I have the simplest tastes. I am always satisfied with the best.” Oscar Wilde

If we look at market figures, then “Gartner 2012 Worldwide RDBMS market share” reports 48.3 percent revenue share for Oracle.

RDBMS_Market_Share

Three major factors make the Oracle database a clear leader:

1. Remains #1 in worldwide RDBMS software revenue share
2. Holds a larger revenue share than four closest competitors combined
3. Leads next closest competitor revenue share by 29%

But why is that so? Let us have a look at the latest DB-Engines Ranking where Oracle is not only #1 in the DB-Engines Ranking of Relational DBMS but also in the Complete Ranking.

The DB-Engines Ranking are measured the popularity of a system by using the following parameters:

– Number of mentions of the system on websites, measured as number of results in search engines queries.
– General interest in the system.
– Frequency of technical discussions about the system.
– Number of job offers, in which the system is mentioned.
– Number of profiles in professional networks, in which the system is mentioned.

What is the best relational database? The best answer given in answers.yahoo.com is the following: “Define “best”. Oracle is like a BMW. Expensive but has all the fixings. But not everyone needs a BMW. MySQL is like a VW Beetle (the old model). Its cheap, and gets you where you need to go. But you have to tweak it to suit your needs.” Nice explanation!

Next, let us look at Gartner’s Magic Quadrant for Data Warehouse Database Management Systems from January 31st, 2013:

Gartner_Magic_DW

The reason Oracle is top on the “Ability to Execute” scale is simple. It can be described by me with just one word: Exadata. Of all the vendors in this analysis, Oracle reports the highest incidence of nontraditional analytics customers: sectors such as hospitality, energy trading, life sciences and food distribution show up in its reference base. According to Gartner, many of the vertical markets where Oracle has the greatest success contain traditional implementers or late adopters of data warehousing. Oracle’s customers range in annual revenue from $100 million to over $10 billion.

The Business Technology Forum raised the same question: Which is the best enterprise RDBMS database? The article is very much to the point coming to the conclusion that Oracle have the upper hand.

Mirror, Mirror on the Wall, which is the best RDBMS of all? You do not expect an answer from the Mirror “It depends” because anyone trying to be diplomatic will answer that way. Well, at least they say that Oracle is most scalable, most feature rich, and just a wonderful RDBMS.

More to read:

Why would you use Oracle database?
Why Oracle is the Preferred Database Platform?
Is Microsoft’s SQL Server really cheaper than Oracle?

The last one favors SQL Server over Oracle but a word of caution on the credibility on the Oracle side: the author calls PL/SQL “P-SQL” and refers to Active Data Guard as “Advanced Data Guard”.

It will take DB2, SQL Server, Sybase, PostgreSQL and all other key RDBMS players at least several more releases before they can approach the current self-management and tuning capabilities of Oracle Database 11g. But when that day comes, Oracle will not be still at version 11.2.0.

12c is knocking on the door.

Oracle12c

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GoldenGate enters the Oracle database

In DBA, Golden Gate, MySQL, Oracle database, Replication, Sybase on June 1, 2011 at 00:02

A friend of mine claims that GoldenGate is a product that is supposed to be used and exist outside the Oracle database. And if you run Oracle on a version below 11.2.0.2, the following query for GOLDENGATE objects will probably return no rows selected. But here is what happens with Oracle 11.2.0.2:

Interesting, right ?

Note that recently Oracle GoldenGate 11.1.1.1 was released. For Oracle GoldenGate on Oracle versions 10gR2 and higher, Extract now manages log retention by default. With this new feature, the documentation says you should be aware of the following:

1. The upgrade will automatically register each of your Extract processes with the database, which will start retaining the logs based on the current recovery requirements for each process.

2. An Oracle Streams Capture process will be created for each Extract process and will have the same name as that process. These Capture processes are non-functional and can operate concurrently with other local Oracle Streams installations.

3. In order for the upgrade to succeed (on 11.2.0.2), you will need to assign the Extract user some additional privileges.

Note first that you need to commit after executing the procedure in the dbms_goldengate_auth package:

SQL> exec dbms_goldengate_auth.grant_admin_privilege('GGATE');
PL/SQL procedure successfully completed.
SQL> commit work;
Commit complete.

Note additionally that the privilege_type can be CAPTURE, APPLY or BOTH. Both (= *) is the default. If you prefer that the GGATE user is granted also the select_catalog_role, you should run the command like this:

SQL> exec dbms_goldengate_auth.grant_admin_privilege('GGATE','*',TRUE);
PL/SQL procedure successfully completed.
SQL> commit work;
Commit complete.

Oracle GoldenGate version 11.1.1.1 contains improved sequence support. To enable this support, you must install some database procedures that support the new FLUSH SEQUENCE command. I recommend that for details you read Samuel Oleleh’s Oracle Goldengate 11.1.1.1 Sequence Support article.

The (Oracle database related) new features of GoldenGate 11.1.1.1 are very well described in the following blob entries:

1. Oracle GoldenGate version 11.1.1.1 new features by Samuel Oleleh.
2. Oracle GoldenGate version 11.1.1.1 released by Miladin Modrakovic.

For all the MySQL users (are there any?), I will note that there is a new ALTLOGDEST option that was added to TRANLOGOPTIONS to specify the location of the MySQL log index file. This value overrides the database default location. Extract reads the log index file to find the binary log file that it needs to read.

For the Sybase users I will mention that the range of values for DBOPTIONS TDSPACKETSIZE has been changed. Additionally, two formerly internal parameters are now available for use in a TRANLOGOPTIONS statement:
– TRANLOGOPTIONS MAXREADSIZE specifies how many records Extract reads from the transaction log at one time. It can be used to improve performance.
– TRANLOGOPTIONS READQUEUESIZE specifies the internal queue size, in bytes, for transaction data. It can be increased to improve performance.

For Oracle GoldenGate installations please check:

1. Pythian’s Oracle GoldenGate Installation, Part 1
2. Pythian’s Oracle GoldenGate Installation, Part 2

As I hinted above MySQL and GoldenGate do not in my opinion go hand in hand. But I would briefly like to mention that Oracle GoldenGate can be used together with Active Data Guard to achieve almost zero planned and/or non-planned down time:

I will soon write more on live upgrades, zero downtime and 100% SLAs 🙂

P.S. As of today, Google returns only two pages with results for dba_goldengate_privileges, try for yourself to see if things have already changed: