How to disable and reenable constraints in Oracle

Disable
1. Run this script in your sql editor and output the results

select 'ALTER TABLE '||substr(c.table_name,1,35)||
' DISABLE CONSTRAINT '||constraint_name||' CASCADE;'
from user_constraints c, user_tables u
where c.table_name = u.table_name;

2. Copy paste the results and run them in your SQL editor again


Enable
1. Run this script in your sql editor and output the results

select 'ALTER TABLE '||substr(c.table_name,1,35)||
' ENABLE CONSTRAINT '||constraint_name||' ;'
from user_constraints c, user_tables u
where c.table_name = u.table_name;

2. Copy paste the results and run them in your SQL editor again

Delete all rows in Oracle database

1. Run this:
select 'delete from ', table_name, '; ' from user_tables;

2. run and script the output into a file.

3. copy paste the commands from the file into your SQL editor.

done

Oracle: Drop all tables in the present schema

1. Login as the desired user
2. Issue this SQL

select 'drop table ', table_name, 'cascade constraints ;' from user_tables;

3. You will then get a list of drop table commands.
4. Just copy/paste into an SQL editor of your choice and run the whole batch of scripts

Uninstall Oracle....the easy way

Try this...quick and painless

run this> $ORACLE_HOME/oui/bin/runInstaller

Select "Installed Products"

Select and click "Remove"

Voila

Reg Ex to validate comma delimited fields

Here's something that I cooked up that perhaps someone could find useful.

[\\w\\d]*(,[\\w\\d]*)*

e.g input asdf123,asdf234,asdf2134

no spaces between commas so that saves you from having to trim later.

Look for text in files recursively in Ubuntu

grep -r "text to search" /directoryToSearch

Maven plugin ClassNotFoundException

Maven plugins use their own class loader which does not include the current projects class loader. To get the plugin to reference the class loader,

• include the outputDirectory of the current project into a new URLClassLoader which has the present threads context loader as its parent
  
• include all references to classes loaded at the current project to include this new classloader
  
• do this at the execute() method of the Mojo.

try {

File classesFolder = new File(this.outputDirectory,"classes");

URL[] urls = new URL[]{classesFolder.toURI().toURL()};
URLClassLoader classLoader = new URLClassLoader(urls, (URLClassLoader)Thread
.currentThread().getContextClassLoader());

Thread.currentThread().setContextClassLoader(classLoader);


} catch (MalformedURLException e1) {
System.out.println("[Fatal Error] Unable to create custom classloader for project");
e1.printStackTrace();
System.exit(0);
}

where outputDirectory is
/**
* Location of the file.
* @parameter expression="${project.build.directory}"
* @required
*/
public static File outputDirectory;

and classes within the plugin that that attempts to load classes within the current project should so something like the following

something like this:
theClass = Class.forName(className,true,Thread.currentThread().getContextClassLoader());