JDBC Environment Setup. To start developing with JDBC, you should setup your JDBC environment by following the steps shown below. We assume that you are working on a Windows platform. Install Java. Install J2. PgAdmin III. QA for database professionals who wish to improve their database skills and learn from others in the community. Please note Cookies should be enabled for the download process to function properly. PostgreSQL, often simply Postgres, is an objectrelational database management system ORDBMS with an emphasis on extensibility and standards compliance. SE Development Kit 5. JDK 5. 0 from Java Official Site. Q7bAluS1Q/hqdefault.jpg' alt='Pgadmin Iii' title='Pgadmin Iii' />Make sure following environment variables are set as described below JAVAHOME This environment variable should point to the directory where you installed the JDK, e. C Program FilesJavajdk. CLASSPATH This environment variable should have appropriate paths set, e. C Program FilesJavajdk. PATH This environment variable should point to appropriate JRE bin, e. C Program FilesJavajre. It is possible you have these variable set already, but just to make sure heres how to check. PgAdminCreateScriptRunStart.jpg' alt='Pgadmin Iii' title='Pgadmin Iii' />. Linux su postgres bash3. U postgres postgresalter user postgres with password new password postgresq. Hide Window Plus License Key on this page. Spatial_Database_Lab1_PostgreSQL+Tutorial+I_GUI.pdf&attachmentId=40174309&attachmentVer=1&pageId=39948127&slide=0' alt='Pgadmin Iii' title='Pgadmin Iii' />Go to the control panel and double click on System. If you are a Windows XP user, it is possible you have to open Performance and Maintenance before you will see the System icon. Go to the Advanced tab and click on the Environment Variables. Now check if all the above mentioned variables are set properly. You automatically get both JDBC packages java. J2. SE Development Kit 5. JDK 5. 0. Install Database. The most important thing you will need, of course is an actual running database with a table that you can query and modify. Install a database that is most suitable for you. You can have plenty of choices and most common are My. SQL DB My. SQL is an open source database. You can download it from My. SQL Official Site. We recommend downloading the full Windows installation. In addition, download and install My. SQL Administrator as well as My. SQL Query Browser. These are GUI based tools that will make your development much easier. Finally, download and unzip My. SQL ConnectorJ the My. SQL JDBC driver in a convenient directory. For the purpose of this tutorial we will assume that you have installed the driver at C Program FilesMy. SQLmysql connector java 5. Accordingly, set CLASSPATH variable to C Program FilesMy. SQLmysql connector java 5. Your driver version may vary based on your installation. Postgre. SQL DB Postgre. SQL is an open source database. You can download it from Postgre. SQL Official Site. The Postgres installation contains a GUI based administrative tool called pg. Admin III. JDBC drivers are also included as part of the installation. Oracle DB Oracle DB is a commercial database sold by Oracle. We assume that you have the necessary distribution media to install it. Oracle installation includes a GUI based administrative tool called Enterprise Manager. JDBC drivers are also included as a part of the installation. Install Database Drivers. The latest JDK includes a JDBC ODBC Bridge driver that makes most Open Database Connectivity ODBC drivers available to programmers using the JDBC API. Now a days, most of the Database vendors are supplying appropriate JDBC drivers along with Database installation. So, you should not worry about this part. Set Database Credential. For this tutorial we are going to use My. SQL database. When you install any of the above database, its administrator ID is set to root and gives provision to set a password of your choice. Using root ID and password you can either create another user ID and password, or you can use root ID and password for your JDBC application. There are various database operations like database creation and deletion, which would need administrator ID and password. For rest of the JDBC tutorial, we would use My. SQL Database with username as ID and password as password. If you do not have sufficient privilege to create new users, then you can ask your Database Administrator DBA to create a user ID and password for you. Create Database. To create the EMP database, use the following steps Step 1. Open a Command Prompt and change to the installation directory as follows. C cd Program FilesMy. SQLbin. C Program FilesMy. SQLbin. Note The path to mysqld. My. SQL on your system. You can also check documentation on how to start and stop your database server. Step 2. Start the database server by executing the following command, if it is already not running. C Program FilesMy. SQLbin mysqld. C Program FilesMy. SQLbin. Step 3. Create the EMP database by executing the following command. C Program FilesMy. SQLbin mysqladmin create EMP u root p. Enter password. C Program FilesMy. SQLbin. Create Table. To create the Employees table in EMP database, use the following steps Step 1. Open a Command Prompt and change to the installation directory as follows. C cd Program FilesMy. SQLbin. C Program FilesMy. SQLbin. Step 2. Login to the database as follows. C Program FilesMy. SQLbin mysql u root p. Enter password. Step 3. Create the table Employee as follows. EMP. mysql create table Employees. Query OK, 0 rows affected 0. Create Data Records. Finally you create few records in Employee table as follows. INSERT INTO Employees VALUES 1. Zara, Ali. Query OK, 1 row affected 0. INSERT INTO Employees VALUES 1. Mahnaz, Fatma. Query OK, 1 row affected 0. INSERT INTO Employees VALUES 1. Zaid, Khan. Query OK, 1 row affected 0. INSERT INTO Employees VALUES 1. Sumit, Mittal. Query OK, 1 row affected 0. For a complete understanding on My. SQL database, study the My. SQL Tutorial. Now you are ready to start experimenting with JDBC. Next chapter gives you a sample example on JDBC Programming. Postgre. SQL Wikipedia. Postgre. SQL, often simply Postgres, is an object relational database management system ORDBMS with an emphasis on extensibility and standards compliance. Lost Planet Extreme Condition Colonies Serial on this page. As a database server, its primary functions are to store data securely and return that data in response to requests from other software applications. It can handle workloads ranging from small single machine applications to large Internet facing applications or for data warehousing with many concurrent users on mac. OS Server, Postgre. SQL is the default database 1. Microsoft Windows and Linux supplied in most distributions. Postgre. SQL is ACID compliant and transactional. Postgre. SQL has updatable views and materialized views, triggers, foreign keys supports functions and stored procedures, and other expandability. Postgre. SQL is developed by the Postgre. SQL Global Development Group, a diverse group of many companies and individual contributors. It is free and open source, released under the terms of the Postgre. SQL License, a permissive software license. Postgre. SQLs developers pronounce Postgre. SQL as. 1. 5 It is abbreviated as Postgres because of ubiquitous support for at least early version of the SQL standard among most relational databases. Postgre. SQL implements features of old and up to later versions. Originally named POSTGRES, the name Post Ingres refers to the projects origins in that database which was developed at University of California, Berkeley. The community considered changing the name back to Postgres however, the Postgre. SQL Core Team announced in 2. Postgre. SQL. 1. 8HistoryeditPostgre. SQL evolved from the Ingres project at the University of California, Berkeley. In 1. 98. 2, the leader of the Ingres team, Michael Stonebraker, left Berkeley to make a proprietary version of Ingres. He returned to Berkeley in 1. Ingres project to address the problems with contemporary database systems that had become increasingly clear during the early 1. The new project, POSTGRES, aimed to add the fewest features needed to completely support types. These features included the ability to define types and to fully describe relationships  something used widely before but maintained entirely by the user. In POSTGRES, the database understood relationships, and could retrieve information in related tables in a natural way using rules. POSTGRES used many of the ideas of Ingres, but not its code. Starting in 1. 98. POSTGRES team published a number of papers describing the basis of the system, and by 1. ACM SIGMOD Conference. The team released version 1 to a small number of users in June 1. June 1. 99. 0. Version 3, released in 1. By 1. 99. 3, the great number of users began to overwhelm the project with requests for support and features. After releasing version 4. June 3. 0, 1. 99. Berkeley had released POSTGRES under an MIT style license, which enabled other developers to use the code for any use. At the time, POSTGRES used an Ingres influenced POSTQUEL query language interpreter, which could be interactively used with a console application named monitor. In 1. 99. 4, Berkeley graduate students Andrew Yu and Jolly Chen replaced the POSTQUEL query language interpreter with one for the SQL query language, creating Postgres. The front end program monitor was also replaced by psql. Yu and Chen announced the first version 0. May 5, 1. 99. 5. Version 1. Postgres. 95 was announced on September 5, 1. On July 8, 1. 99. Marc Fournier at Hub. Networking Services provided the first non university development server for the open source development effort. With the participation of Bruce Momjian and Vadim B. Mikheev, work began to stabilize the code inherited from Berkeley. In 1. 99. 6, the project was renamed to Postgre. SQL to reflect its support for SQL. The online presence at the website Postgre. SQL. org began on October 2. The first Postgre. SQL release formed version 6. January 2. 9, 1. 99. Since then a group of developers and volunteers around the world have maintained the software as The Postgre. SQL Global Development Group. The Postgre. SQL project continues to make major releases approximately annually and minor bugfix releases, all available under its free and open source software Postgre. SQL License. Code comes from contributions from proprietary vendors, support companies, and open source programmers at large. DevelopmenteditPostgre. SQL does not have a bug tracker while it has a bug submission form that feeds into the pgsql bugs mailing list, making it quite difficult to know the status of bugs. Multiversion concurrency control MVCCeditPostgre. SQL manages concurrency through a system known as multiversion concurrency control MVCC, which gives each transaction a snapshot of the database, allowing changes to be made without being visible to other transactions until the changes are committed. This largely eliminates the need for read locks, and ensures the database maintains the ACID atomicity, consistency, isolation, durability principles in an efficient manner. Postgre. SQL offers three levels of transaction isolation Read Committed, Repeatable Read and Serializable. Because Postgre. SQL is immune to dirty reads, requesting a Read Uncommitted transaction isolation level provides read committed instead. Postgre. SQL supports full serializability via the serializable snapshot isolation SSI technique. Storage and replicationeditReplicationeditPostgre. SQL includes built in binary replication based on shipping the changes write ahead logs to replica nodes asynchronously, with the ability to run read only queries against these replicated nodes. This allows splitting read traffic among multiple nodes efficiently. Earlier replication software that allowed similar read scaling normally relied on adding replication triggers to the master, introducing additional load onto it. Postgre. SQL also includes built in synchronous replication2. Unlike other database systems, the durability of a transaction whether it is asynchronous or synchronous can be specified per database, per user, per session or even per transaction. This can be useful for work loads that do not require such guarantees, and may not be wanted for all data as it will have some negative effect on performance due to the requirement of the confirmation of the transaction reaching the synchronous standby. There can be a mixture of synchronous and asynchronous standby servers. A list of synchronous standby servers can be specified in the configuration which determines which servers are candidates for synchronous replication. The first in the list which is currently connected and actively streaming is the one that will be used as the current synchronous server. When this fails, it falls to the next in line. Synchronous multi master replication is currently not included in the Postgre. SQL core. Postgres XC which is based on Postgre. SQL provides scalable synchronous multi master replication,2. April 2. 01. 5 version is licensed under the same license as Postgre. SQL. A similar project is called Postgres XL. Postgres R is yet another older fork. Bi directional replication BDR is an asynchronous multi master replication system for Postgre. SQL. 2. 8The community has also written some tools to make managing replication clusters easier, such as repmgr. There are also several asynchronous trigger based replication packages for Postgre.