Wednesday, January 18, 2012

How to show only one header in sqlplus

When you have to use sqlplus and want to avoid showing table header each n rows returned, you can use the command bellow to show only one header:


set pagesize 0   -- only one header row

Another useful commands:
set colsep ,     -- separate columns with a comma
set trimspool on -- remove trailing blanks
set headsep off  -- this may or may not be useful...depends on your headings.
set linesize X   -- X should be the sum of the column widths

sqlplus reference: http://psoug.org/reference/sqlplus.html
How to create a csv file from sqlplus output: http://stackoverflow.com/questions/643137/how-do-i-spool-to-a-csv-formatted-file-using-sqlplus


Wednesday, January 4, 2012

How to generate Java classes for Hibernate from MySql database tables using Eclipse Indigo


  1. Install JBoss Tools on Eclipse using update site
    In Eclipse Indigo, on menu bar, click Help / Install new Software
    Paste this address in Work with text field and click Add... http://download.jboss.org/jbosstools/updates/development/indigo/
    The mandatory plugin is JBoss Data Services / Hibernate tools, but it is good to install all of them
  2. Create a Hibernate Configuration
    Open Hibernate Perspective
    In Hibernate Configurations panel, right click in a empty space and go to Add Configuration
    In Project field, select the project where Java classes will be created.
    In Database Connection combo box select an existent MySql connection or create a new one clicking on New button.
    In Property file field, click in Setup / Create new
    In Configuration file field, click in Setup / Create new
    Click OK
  3. Run Hibernate Code Generation
    Edit hibernate.cfg.xml file. Remove name property on session-factory tag. Let it with no attributes.
    Add hibernate-tools.jar to the project classpath. It can be found at <eclipse installation folder>\plugins\org.jboss.tools.hibernateextension4_0_3.4.0.v20111213-1944-H40-M5\lib\tools
    On Hibernate perspective, on menu bar, click Run / Hibernate Code Generation /  Hibernate Code Generation Configurations
    In Console configuration, select the just created configuration
    In Output directory, select the source root folder
    In Package, type desired package
    In revenge.xml, click Setup / Create new
    In reveng. strategy, Browse to the class org.hibernate.cfg.reveng.DefaultReverseEngineeringStrategy
    Click Run button
  4. Check generated classes out
    Open Java EE perspective
    Refresh project files
    See that entity and DAO classes were generated