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SED Command

SED ( Stream editor) : A special editor for modifying files automatically. It has similarity with the “Find” and “Replace” command available in windows notepad/wordpad. sed command can be used to search and manipulate input text in many ways. Though mainly used for substitution, it can also do numerous other …

Classification of UNIX Commands

There are more than 200 UNIX level commands. The important ones are classified below: General Purpose Utilities passwd who whoami uname tty stty info Working With Directories mkdir rmdir ls File Handling Commands cat cp rm mv more wc cmp diff dos2unix tar gzip AND gunzip compress AND uncompress zip …

AWK Command

Awk actually stands for the names of its authors: “Aho, Weinberger, & Kernighan”. Used for pattern scanning / filtering Command syntax :   awk  <search pattern> { action } Example : Consider the file test.log with the below data server501:[DATA001] /home/oracle -> cat test.log ANJELINA IS A GOOD GIRL RAMU …

UNIX Architecture

UNIX Architecture can be best understood if we know the components in UNIX. The important components of UNIX OS can be classified as below. 1. Kernel – small program written i n C which interacts with hardware 2.Shell (Command Interpretor) – One shell is generated for each user for running commands. Bourne shell(sh) is …

Aakash Tablet – Why Should You Buy It?

The new sector of Tablet PCs has emerged, and masses are showing great enthusiasm at these new size gadgets. A range of gadgets are now available in the market ranging from iPad 2 to the  cheapest Aakash Tablets. iPad 2 without 3G costs around $499(Rs.25000) but the Aakash Tablet from …

What is BioTechnology? Products, Effects and Jobs

What is Biotechnology? How will you define Biotechnology? Biotechnology can be defined as a technology applied on living organisms (mainly at the cellular or molecular level) to alter their normal life processes to produce useful products or effects which has industrial, commercial or medical relevance. Useful Products of Biotechnology: Pharmaceutical products …

What Are The Basic UNIX Ulilities / Commands?

pwd                                       print working directory cd                                           change directory mkdir                                    make directory rmdir                                     remove directory ls                                             list contents of directory cat                                          display contents of files cp                                           copy one file to another rm                                          remove files tput clear                           clear screen who                                       …

What is UNIX?

UNIX is the  trademarked form of Unics (Uniplexed Information and Computing System). UNIX is an important Operating System developed in 1969 by AT &T. Dennis Ritchie and Ken Thompson were the brains behind this OS. Though the  name UNIX is trademarked , UNIX is more like a family name now, …

What is Oracle – Meaning of the word Oracle

The word “Oracle” means – An authoritative person who divines the future . Oracle is  believed to be infallible. Oracle Corporation is software-hardware company whose main product is Oracle Database Software. Oracle Database Software is used to produce databases. Oracle software is proprietary, but they also owns the MySQL database software, …

Why Can’t I Access My Gmail Account?

There can be many reasons for your lack of access to your gmail account. It can be username, password or hacking issues. Date and Time Settings of the system can be another reason too, which we are discussing here. Date and Time Settings of the system: If you have enabled …

Find Blocking Session, Locks, Waiting Session of Database

SQL> select l1.sid, ‘ IS BLOCKING ‘, l2.sid from v$lock l1, v$lock l2 where l1.block =1 and l2.request > 0 and l1.id1=l2.id1 and l1.id2=l2.id2; SQL> SELECT SID, DECODE(BLOCK, 0, ‘NO’, ‘YES’ ) BLOCKER, DECODE(REQUEST, 0, ‘NO’,’YES’ ) WAITER FROM V$LOCK WHERE REQUEST > 0 OR BLOCK > 0 ORDER BY …

How To Check If Database Got Corrupted?

Datablock level Corruption can be found out with the help of the following two queries. SQL> SELECT distinct ‘Data Block# ‘|| block# || ‘ of Data File ‘ || name || ‘ is corrupted.’ FROM v$backup_corruption a, v$datafile b WHERE a.file# = b.file#; 2 3 4 no rows selected SQL> …