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Archive for the ‘Replication’ Category

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:

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Watson, IBM InfoSphere Streams and Oracle Streams

In DB2 database, Grid Control, Oracle database, Replication on February 24, 2011 at 19:30

Initially, my plan was to write only on Oracle Streams but after Watson’s victory on Jeopardy, I got an interesting question from an ex-colleague of mine: Is this supercomputer HA? What if the database crashes and there is no source for answers? Funny, isn’t it 🙂 After all Watson is an example of an analytics workload optimized system, not an online sales platform.

But first, have a look at this, how Ken Jennings and Brad Rutter, the show’s two biggest winners, took on their database rival on Feb. 14-16 2011. Note that according to the president of WABC – New York City’s ABC television affiliate Monday’s broadcast of the IBM Watson/Jeopardy Challenge was the most watched show on any channel in the NY Metro area.






Watson is a mixture of 10 racks of IBM POWER 750 servers, Linux OS, 15 TB of RAM, 2880 processor cores and operates at 80 teraflops. The data is stored in a DB2 database. Another one of the 4 major technologies Watson is based on is IBM InfoSphere Streams. While IBM InfoSphere Streams enables continuous and super fast analysis of massive volumes of information, Oracle Streams enables continuous and very fast replication of massive volumes of information. Well, at least when it works and there are no errors. Say one like this:

Looking at the details of the error, what do we understand?

As much as we understand from the statistics:

My personal opinion is that Streams is as good as Advanced Replication was. After all, Oracle will not develop it any longer. Oracle bought Golden Gate and will try to use it for all data integration/replication solutions.

P.S. If only Sherlock Holmes had this type of Watson 🙂

The quality of the Oracle database product

In Bugs, DBA, Oracle database, RAC, Replication on January 4, 2011 at 10:19

Two major things have recently caught my attention. They are more like strategic and of long term importance for the Oracle database.

1. Real online patching and database upgrades are still happening mostly on power point presentations. They should not be dependent on database types, patch type, version, replication, etc. and should be in DBA terms simple.

Top Google searches for Oracle database live upgrades relate rather to certification upgrades, not database upgrades:

Does Oracle have zero downtime maintenance, have a look:

Is Oracle Golden Gate similar to QREP in IBM’s DB2?

2. Product quality of all database components is getting worse and worse all the time.

– Look at the 10.2.0.5 bug fixes: they are just too many!
– The following three components throw too many errors and bugs: all types of replication, RAC and Grid Control
– ORA-600 pops up too often nowadays!