Flex ASM (New feature on 12c)

Starting with 12c, there is a new exciting feature. Oracle Flex ASM enables an Oracle ASM instance to run on a separate physical server from the database servers.

You have the possibility of having only one ASM instance for all yours database instances. This allows cost savings and management with respect to 10g and 11i, where you need to have an ASM instance per server where there is ASM

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Merge execution fails with: ORA-01555 on Siebel Upgrade

I am currently involved in a Siebel upgrade from version 7 to version 8 (8.1.1.10). One of the problems I have found is relative to UNDO. The problem is an ORA-01555: snapshot too old: rollback segment number …

Since UNDO appeared as  substitute of  Rollback Segment this kind of error has  greatly reduced. Researching the subject, there is a note from Siebel  ID 477025.1, You can it in My Oracle Support  (formerly known as Metalink) detailing the error. The solution has been disable UNDO (setting it to manual) and create a large Rollback Segment.

 

 

UPGRADE TO OCP 12c

Now available in beta, the 1Z1-060 exam, this gives access to 12c from OCP  9i, 10g or 11g. More information is available here.

If you do not own the OCP, you must first get 12c OCA certification. In this case it is necessary to pass  1Z0-061, 1Z0-062 and 1Z0-063 exams.

Here you can download database engine  (Release 12.1.0.1.0)

In this link is the documentation

Good luck.

 

 

 

 

 

 

 

SQL Tagging to trace queries in Siebel

Starting with Siebel Fix Pack 8.1.1.1 and later, SQL tagging feature provides the ability to trace the origin of long-running or slow-performing SQL statements. After SQL tagging is enabled (from Siebel), tagging information is added to the Siebel Application Object Manager. This feature is only available for SELECT. Other statements such as INSERT, UPDATE, DELETE or MERGE are not tagged.

 

SQL Tagging Format

SQL tagging information is formatted as a comma-separated list of values using the following syntax:
<componentname>,<servername>,<taskid>,<userid>,<flowid:sarmid>,<busobjname>,<buscompname>,<viewname>

 

where:

  • componentname is the alias of the component.
  • servername is the name of the Siebel Server on which the component or task is running.
  • taskid is the task ID of the user who generated the query.
  • userid is the login name of the user who generated the query.
  • flowid is the flow ID of the component or task.
  • sarmid is the SARM ID of the component or task.
  • busobjname is the business object name.
  • buscompname is the business component name.
  • viewname is the view name.

 

The tagged sql is returned as bind variable inside the <select list>, in the nth position, before the FROM clause. It will the bind variable label as :1, the rest of the statement will as usual. FROM clause, WHERE clause and ORDER (if exist). Note that the SQLID in Oracle SQL Tagging sentence will be different from a sentence without SQL Tagging.

 

sql_tagging_format

 

Database link and event “single-task message”

Today I had a problem with a private database link between two databases. The user reports that running a simple “desc dual@pluto.cartoons.com” doesn’t work.  Currently in the source database are three sessions hung. If we look at that do these sessions, we can see that are waiting for the event single-task message.

foto1

This event usually occurs across the database link connection. We tried to perform a tnsping to check the listener.

foto2

Tnsping command doesn’t reply, so we can determine that the problem is the listener, try perform a lsnrctl status but not responding so we opted to finish the process with the command “kill -9” since we are on unix platform and restart the listener. In the source database the first three sessiones continue unanswered so we kill, in this case from database.

foto3

The kill command reply “ORA-00031: session marked for kill”. The sessions continue but do not die, so we kill them using kill command from Operating System .

Get IP-Address in RAC interconnect from Oracle Instance.

Sometimes we have no access to the clusterware and we need to verify or find out the IP of the NIC interconnect. We can get this information in a simple way because Oracle provides two Oracle views, V$CLUSTER_INTERCONNECTS and V$CONFIGURED_INTERCONNECTS.

V$CONFIGURED_INTERCONNECTS displays all the interconnects that Oracle is aware of and where Oracle found the information about a specific interconnect. This view have four attributes.

  • NAME, name of the interconnect (such as eth0)
  • IP_ADDRESS, IP address of the interconnect
  • IS_PUBLIC, if the value is YES, the interface is known to the public. If the value is NO to be private
  • SOURCE, indicates where Oracle found the information. CLUSTER_INTERCONNECTS parameter, Oracle Cluster Repository (OCR) or Operating-system dependent software

 

Example in active/active

We connect to all the nodes that make up the cluster and execute the following statement .(In this case there are only two nodes).

rac_x_1

 

Example in active/passive

In this case there is only one instance so we will only get the NIC configured where the instance is running.

rac_x_2