Santosh Kangane

For critical OLTP applications system wide down time is absolutely no-no. Also handling the Software faults (Especially bugs in underdevelopment application), How to allow user to perform UAT while they are working on their routine operations? Common solution that almost every social web application uses, pilot releases and let only selected region of the user test the system.  But can that be possible in database heavy operational systems? Such as Banking, Supply chain management, Income tax returns, accounting where database is heart of the business and let you not miss even single byte of data. Here is our small approach which we used for Supply chain management system and rolled out across all India seamlessly... This we did on Oracle database (And it can be extended to almost all the databases with littlie changes – with equivalent to Oracle schema concept). So here it is... 1. You have all the tables created in single set of schemas, which will hold only data tables...

Installation of P4 : 1. Download setup and Mark p4 as executable:   -bash-3.2$ pwd /data/home/ admin /santosh / softlib -bash-3.2$  wget http://www.perforce.com/downloads/perforce/r12.2/bin.linux26x86_64/p4 -bash-3.2$  chmod +x p4 -bash-3.2$  ls -l total 2376 - rwxr - xr -x 1 admin   admin 2431784 Oct 16 12:20 p4 2. Copy p4 under /use/local/bin -bash-3.2$ which p4 / usr /bin/which: no p4 in (/opt/jdk1.6.0_21 //bin:/usr /kerberos /bin:/usr /local/bin:/bin:/usr /bin) -bash-3.2$  sudo cp  p4 / usr /local/bin/ We trust you have received the usual lecture from the local System Administrator. It usually boils down to these three things:     #1) Respect the privacy of others.     #2) Think before you type.     #3) With great power comes great responsibility. [ sudo ] password for admin : -bash-3.2$ which p4 / usr /local/bin/...

Simple steps to remove Oracle instance…. 1) Login to the server machine with Oracle user 2) Set ORACLE_HOME, ORACLE_SID 3) Open SQL Plus [oracle$] sqlplus / as sysdba SQL> shutdown immediate Database closed. Database dismounted. ORACLE instance shut down. SQL> startup mount EXCLUSIVE ORACLE instance started. Total System Global Area 3.2068E+10 bytes Fixed Size                  2214736 bytes Variable Size            1.5838E+10 bytes Database Buffers         1.6106E+10 bytes Redo Buffers              122404864 bytes Database mounted. SQL> alter system enable restricted session; System altered. SQL> drop database; Database dropped. Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 ...

To verify the SQL Server setup compliance with Microsoft Best Practices has become more easier now. Microsoft has provided “SQL Server 2008 R2 Best Practices Analyzer” tool. One can install following two components on Server or any remote machine (additional settings will required in 2nd case) 1) Microsoft® SQL Server® 2008 R2 Best Practices Analyzer 2) Microsoft Baseline Configuration Analyzer 2.0 On Execution tool will detail out the compliance report as per the Microsoft’s best recommended practices. To tune any SQL Server we can use this as startup point…   

I thought, setting up Distributed, NOSQL, Big Data must be a complex process. However, when I actually did it for cassandra, I found it like installing some simple OS package !!!.. Cassandra is too simple to setup and play around it. I found it more like plug and play engine. The Cassandra database very well explained in Book : O’Reilly Cassandra: The Definitive Guide, Nov 2010   So, Here is how to do it…. A) Pre requisites : jdk1.6 or grater version.        If you don’t have, you can download and configure it. How ? B) Cassandra on Linux           1. Create user for cassandra root@PTS0012:/usr/lib# id cassandra uid=506(cassandra) gid=0(root) groups=0(root) root@PTS0012:/usr/lib# 2. Create Dir for cassandra database root@PTS0012:/usr/lib# mkdir -p /var/log/cassandra root@PTS0012:/usr/lib# chown -R cassandra /var/log/cassandra root@PTS0012:/usr/lib# mkdir -p /...

To generate the AWR report: Log in to the machine hosting Oracle server. Connect to Oracle server with SYS or equivalent DBA level access user. At a command prompt, issue the following command: @$ORACLE_HOME/rdbms/admin/ awrrpt.sql << This script will create an interactive session follow the instruction as shown below.>> Specify a format for the report and press Enter . Specify the Database instance on which to run the report by typing in the database ID from the list of instances and press Enter (in most cases there is only one choice, but if there is more than one,  find out which instance hosts the your schema). Type the Inst Num and press Enter . Specify when the report should start: You can choose to enter a numeric value for the most recent number of days (e.g., entry of 1 produces a report on the most recent one day of workload). To have finer unit than days hit enter with no values and a list of snapshots will appear: ...

I installed the Oracle 11g RAC successfully, But when tried connecting from remote client via SCAN, it used to raise ORA-12537. This is the most common issues that the happens with SCAN listener. And there are few common mistakes that generally  cause this issue. . So, here is how we can troubleshoot the connectivity issues with SCAN, and cases out the possibilities. 1)  Check if Local_listener and remote_listener parameter are set properly on all nodes. 2)  The very common issue is with permissions. SCAN will always be created under grid user (Grid cluserware installation user). Oracle will also create one local listener “LISTENER” during grid infrastructure installation. But if that is not present then always make sure that you create a local listener with grid user. This is required to handover the connection between remote and local listener. 3)  Also “oracle” executable should have given to oracle and grid user i.e. 6751.  Under $ORACLE_HOME/bi...