Database Technologies

Since, PostgreSQL 9.1 has already been released and there are lot of new features added in it, so, I thought to blog about each features. Today, I am discussing about Synchronous and Asynchronous Replication supported in PostgreSQL 9.1. For Asynchronous Replication, user can use following method: 1. Change Following Parameters in postgresql.conf file of Primary Database: archive_command = cp -i %p /Users/postgres/archive/%f archive_mode = on max_wal_senders = 3 # Maximum 'wal_senders', processes responsible for managing a connection with a standby server wal_keep_segments = # How many WAL segments (=files) should be kept on the primary, whatever may happen (you won't have to copy them manually on the standby if the standby gets too far behind) wal_level = hot_standby 2. Make Following changes in pg_hba.conf host replication postgres [Ipv4 address of Standby Server]/32 trust host replication postgres [Ipv4 address of Master Server]/32 tr

Today, I thought to share my Training slides on FTS (Full Text Search) in PostgreSQL 9.0. I have used this presentation on giving training. Enjoy :). Full Text Search Training

Depsez has Started a New project called Curo, which is currently made for Unix/Linux and is in initial phase. So, I thought to look at how it works and how normal user, who knows using psql, can benefit from it. Before Installing Curo, user has to make sure, he has postgreSQL client: psql and following package installed on his Linux/Unix System: 1. Bash 2. dialog If you have above required packages on your machine, then you can move for Curo installation. Curo Installation is very simple. Following are the steps which can be use to install Curo on Unix/Linux System: 1. Download the Curo from Following link: https://github.com/omniti-labs/curo Above link will give you file similar to given below: omniti-labs-curo-48a4f31.tar.gz 2. Untar the file using following command: tar -xvf omniti-labs-curo-48a4f31.tar.gz 3. Copy omniti-labs-curo-48a4f31 to users home directory as given below: cp omniti-labs-curo-48a4f31 ~/.curo 4. Now configure .inputrc and .editrc file as given

I had seen people ask Questions about finding the edb-jdbc/postgresql driver version with Database Version. So, I thought to give one java script which can be use to find Database Details with edb-jdbc version. Following is a JAVA Code which can be use to find the Database Version and EDB-JDBC/postgresql-jdbc Version: File Name: DBinfo.java import java.sql.*; public class DBinfo { public static void main(String[] args) { try { Class.forName("com.edb.Driver"); Connection con = DriverManager.getConnection("jdbc:edb://localhost:5444/edb", "enterprisedb","edb"); // Advanced Server Database Connection Information DatabaseMetaData dbmd = con.getMetaData(); System.out.println("===== Database info ====="); System.out.println("DatabaseProductName: " + dbmd.getDatabaseProductName() ); System.out.println("DatabaseProductVersion: " + dbmd.getDatabaseProduc

Logrotator is a small C program which is well written and available on most of the UNIX based OS. It allows automatic rotation, compression of logfiles and removal of old logfiles. This small file can be use to manage applications logfiles. It can also use for managing slony logfiles. For managing logfiles using logrotator user has to make a logrotator conf file, and can be scheduled in crontab for managing logile. Let see how you can make a logrotator configuration file for slony. I have slony master/slave daemon running on my slave maching has following location for slony logfiles: /opt/PostgresPlus/9.0AS/slony_test/slony1/node1 -- For master /opt/PostgresPlus/9.0AS/slony_test/slony1/node2 -- For slave. For managing logfile, user can make logrotator configuration file similar to given below: Configuration filename: /etc/logrotate.d/slonylogfiles "/opt/PostgresPlus/9.0AS/slony_test/slony1/node[12]/*.log" { rotate 5 mail vibhor.aim@gmail.com

Today, I though to mention some of Oracle workarounds which can be use for Migration of Oracle Database to PPAS 9.0(EnterpriseDB). 1. UTL_RAW.CAST_TO_RAW This is a Oracle Packaged Function, which can be use to convert VARCHAR2 value into RAW Value. Lets see its example in Oracle: SQL> select utl_raw.cast_to_raw('TESTING TESTING') from dual; UTL_RAW.CAST_TO_RAW('TESTINGTESTING') -------------------------------------------------------------------------------- 54455354494E472054455354494E47 Since PPAS 9.0, doesn't have this package in 9.0, therefore user can use postgresql function decode() for converting of varchar datatype to RAW/bytea data. Following is an example: edb=# select decode('TESTING TESTING','escape') from dual; decode ---------------------------------- \x54455354494e472054455354494e47 (1 row) which is a same output. 2. UTL_RAW.CAST_TO_VARCHAR2 Using this packaged function user can conver

This has been asked many times, so I thought to write steps for enabling ssl: Following are steps, which can be use to enable ssl in postgreSQL: 1. Generate a passphrase protected certificate using following command: openssl req -new -text -out cert.req Snapshot is given below: Generating a 1024 bit RSA private key ....................++++++ ...................................................++++++ writing new private key to 'privkey.pem' Enter PEM pass phrase: Verifying - Enter PEM pass phrase: ----- You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [AU]: State or Province Name (full name) [Some-State]: Locality Name (eg, city) []: Organization Name