Determining the disk space used by Oracle schema

Run below query to find out how much disk space is being used by an Oracle schema

Select SUM(bytes)/1024/1024/1024 Gb, tablespace_name FROM user_segments GROUP BY tablespace_name;

Memory usage by process

Solaris pmap command provides the memory usage of a process. This command tells you how much of memory a particular process is using and how much of there particular threads/heap are using. It's a very useful command to debug cases where you have to find that who is consuming more memory in your process.

pmap <PID>

example$ pmap 102905
102905: sh
00010000 192K r-x-- /usr/bin/ksh
00040000 8K rwx-- /usr/bin/ksh
00042000 40K rwx-- [ heap ]
FF180000 664K r-x-- /usr/lib/libc.so.1
FF236000 24K rwx-- /usr/lib/libc.so.1
FF23C000 8K rwx-- /usr/lib/libc.so.1
FF250000 8K rwx-- [ anon ]
FF260000 16K r-x-- /usr/lib/en_US.ISO8859-1.so.2
FF272000 16K rwx-- /usr/lib/en_US.ISO8859-1.so.2
FF280000 560K r-x-- /usr/lib/libnsl.so.1
FF31C000 32K rwx-- /usr/lib/libnsl.so.1
FF324000 32K rwx-- /usr/lib/libnsl.so.1
FF340000 16K r-x-- /usr/lib/libc_psr.so.1
FF350000 16K r-x-- /usr/lib/libmp.so.2
FF364000 8K rwx-- /usr/lib/libmp.so.2
FF380000 40K r-x-- /usr/lib/libsocket.so.1
FF39A000 8K rwx-- /usr/lib/libsocket.so.1
FF3A0000 8K r-x-- /usr/lib/libdl.so.1
FF3B0000 8K rwx-- [ anon ]
FF3C0000 152K r-x-- /usr/lib/ld.so.1

Sorting a csv file on a particular field

I have below csv file, which have around 5k lines in following format:

ABC,12345,test.com,56780,0.00,200.65,0.00,0.00,200.65
XYZ,54311,tset.com,69540,0.00,102.32,0.00,0.00,102.32
..
...

I wanted to sort this file on field6 so that i could extract my desired lines from the csv file. I did use below command which sorted my csv file on field no 6:

sort -n -r -t, +6 -7 vishnu.csv

-n Specifies numeric field
-r Reverse sorting
-t specifies seperator (here , is a seperator)
+6, -7 specifies column position

sorting the csv file if separator is tab
sort -t $'\t' -k5 -nr filename

List of tables in the Oracle schema

Wanted to find out list of tables in the Oracle schema? We can use any of the following sql query; which will list all the tables in the specified schema of Oracle database.


SELECT * FROM cat;
SELECT TABLE_NAME FROM TABS;
SELECT * FROM user_objects WHERE object_type = 'TABLE';
SELECT TABLE_NAME FROM ALL_ALL_TABLES;

Execute a perl script from java Program

Interested to execute a perl script from a java program.... uhmmmmm... see below java program (Sample.java)

import java.io.*;

public class Sample{

public static void main(String args[]) {

Process process;

try
{
process = Runtime.getRuntime().exec("perl testscript.pl");
process.waitFor();
if(process.exitValue() == 0)
{
System.out.println("Command Successful");
}
else
{
System.out.println("Command Failure");
}
}
catch(Exception e)
{
System.out.println("Exception: "+ e.toString());
}
}
}

javac Sample.java
java -cp . Sample

compare two sorted files in unix

If you wanted to compare 2 sorted files then use comm command. comm command compares two sorted files line by line. This command reads the File1 and File2 as parameter and writes a three column output to standard output.

First Column: Lines that are only in File1
Second Column: Lines that are only in File2
Third Column: Lines that are in both File1 and File2

Syntax:

comm [-1] [-2] [-3 ] file1 file2

-1 Suppresses the display of the first column (lines in File1)
-2 Suppresses the display of the second column (lines in File2)
-3 Suppresses the display of the third column (lines both in File1 and File2)

Killing a defunct process

A defunct (or "zombie") process is a process that isn't running, isn't eligible to run, and takes up no system resources. It's actually a process that has exited, but its parent has not called wait() in order to find out its exit status.

defunct processes can't be killed since they are already dead. To make them disappear you have to kill their parent process.

Find the parent process id of the defunct process and then kill that parent process:

ps -fe | grep defunctprocess | awk '{print $3}'

kill -9 parentprocessid

Reverse the contents of a file

If you wanted to reverse the contents of a file, use below perl script:


#!/usr/bin/perl

$filename = "a.java";
open(INFILE, "<", $filename)
or die "Can't open $filename for reading: $!\n";
my(@content) = <INFILE>;
close(INFILE);
while (@content) {
my($line) = pop(@content);
chomp $line;
print reverse($line)."\n";
}

Reversing a file

You have a file and you wanted to reverse it. How to do it? Guys...... its really very easy.. Use below commands:


tail -r filename
or
cat -n filename | sort -nr | cut -c8-

You can achieve the same by writing a perl script. See below perl script:


#!/usr/bin/perl

$filename = "a.java";
open(INFILE, "<", $filename)
or die "Can't open $filename for reading: $!\n";
my(@content) = <INFILE>;
close(INFILE);
while (@content) {
my($line) = pop(@content);
chomp $line;
print "$line \n";
}

Zephyr - A Test Management Tool

Recently i got an email from Zephyr regarding their new product launch. Zephyr is basically a Test Management tool aimed at global SME, IT departments and Testing Vendors which helps the testing team to manage their test cases and provide test cases visibility at all levels using a central repository. I checked their product demo which looks cool.
http://www.getzephyr.com/