Database Technologies: Some trigger and programming feature in PostgreSQL

Database Technologies: Some trigger and programming feature in PostgreSQL

Comments

Post a Comment

Popular posts from this blog

UPSERT/MERGE using Writable CTE in PostgreSQL 9.1

There is always discussion of having UPSERT/MERGE in postgresql. Since, oracle and other RDBMS has this feature, therefore people ask about this feature in PostgeSQL. In previous version of PostgreSQL, we used to implement it using functions. Now in PostgreSQL 9.1, user can implement this feature using Writable CTE. PostgreSQL 9.1, now has Writable CTE using WTH. WITH provides a way to write auxiliary statements for use in a larger query. These statements, which are often referred to as Common Table Expressions or CTEs, can be thought of as defining temporary tables that exist just for one query. Each auxiliary statement in a WITH clause can be a SELECT, INSERT, UPDATE, or DELETE; and the WITH clause itself is attached to a primary statement that can also be a SELECT, INSERT, UPDATE, or DELETE. Lets see how we can use Writable CTE for UPSERT. Following are SQL Code which can be use in Oracle and PostgreSQL for creating sample data: For oracle: create table myTable (pid ...
Read more

New in PostgreSQL 9.3: Server Side languages

In series of blogging about new features coming in PostgreSQL 9.3, I thought to blog about the server side language improvements in PostgreSQL. Lets see whats coming in server side language. As PostgreSQL user, you know, PostgreSQL supports multiple server side language. In 9.3, there are some interesting features are coming. Lets look at the new improvements about to come. 1. SPI access to number of rows processed by COPY command. This is more like new feature which is introduced in 9.3. Before 9.3, this feature was missing. i.e if user uses COPY command inside the plperl/plpython functions, then there was no way inside the procedure to trace the number of rows processed by COPY. However in 9.3, this limitation is no more exists with procedural language. There are many languages supported in PostgreSQL, However I chose to test this with mostly used language plperl and plpython. Below are some snapshot pre-9.3 and in 9.3. Lets check with plperl. Following is a plperl function w...
Read more

xDB Replication from Oracle to PPAS

EnterpriseDB Replication tool has been now modified and add new functionality in it. Previous Replication Console, which had been made, was using the DBA Management server and Publication & Subscriptions were dependent. Now, xDB Replication has been divided into two components: 1. Publication Server : (Master Server) 2. Subscription Server: (Slave Server) Some Background of Publication Server. Publication Server has following components: 1. JAVA Based Daemon. 2. MetaDatabase of Publication Server. Publication Server keeps its information (Information about the Primary Database, Tables Details etc.) in the MetaDatabase under schema _edb_replicator_pub Publication server is independent and has no dependency on Subscriptions Server. By default publication server uses the 9011 port. However, if user wants, [S]he can use different ports too. For running Publication Server on different port, use the following command: $EDBHOME/jre/bin/java -Djava.awt.headless=true -jar $...
Read more