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Oracle DBA job

February 23, 2016 Comments off

Why the Oracle DBA job is classified as a complex job

fresher dba jobsThere is a misunderstanding about what exactly the Oracle DBA profession is. Some people assume that this profession depends on technically matter only. The reality is contrasting the assumption as an Oracle DBA is forced to deal with all IT and managerial functions. An Oracle DBA has a maximum responsibility in solving all problems related to the whole of database design, database implementation, backup processes, and recovery ones. Every Oracle DBA needs to have what called excellent communication skills used to communicate with other people in solving one or more IT problems.

To note, Oracle instances are now consolidated onto large server ranging from 32 to 64 CPUs, that results in the decreasing of DBA staffs required. That is the common phenomenon of a relation between increasing technology with the amount of employers. We know background of the use of a lot of CPUs, namely multitasks to be done by DBA. An Oracle DBA needs to manage scheme design as well as other data management tasks. They get a lot of job roles.

The knowledge of Oracle database systems is not the only one needed by an Oracle DBA.

This is the base understanding. An Oracle DBA needs to combine advanced business management knowledge with database knowledge in an intention of performing database activities entirely. The Oracle DBA job needs what called college-level communication skills, formal education, real experiences (some companies requires at least 5 years of experiences), database knowledge, and so forth. The ability of explaining Oracle concepts clearly is the base preferred ability needs to have for every single prospective Oracle DBA. The master-level education degree on information systems is something can’t be compromised. Anyone who has the master-level education degree on information system is expected to solve data normalization as well as star schema design matters. Shortly, the Oracle DBA jobs run a lot of tasks.

Indeed, it is very tough job due to this reason Oracle DBA earns more. Fresher DBA is really encountering to get job and it is not so easy as you are thinking. Every technical interview is very tough and you cannot say that you cleared after finished. There are so many tricky and real time example based queries are being raised during interview. Interviewer always tries to get best candidate from high competitive market. You can get some help from https://goo.gl/UGQk2o

But it doesn’t mean that fresher Oracle DBA never acquire job. Using your depth knowledge and help from some senior DBA you would easily clear technical interview. http://goo.gl/z0Mma8

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What is Reverse Key Index in Oracle?

April 19, 2014 Comments off

Reverse key indexes, as their name involves, robotically reverse the order of the bytes in the key value contained in the B-tree index. If the value in a row is ‘ABCD’, the value for the reverse key index for that row is ‘DCBA’.

To comprehend require for a reverse key index, you have to examination some basic truths about the standard B-tree index. First and primary, the depth of the B-tree is decided by the number of entries in the leaf block nodes. The greater the depth of the B-tree, the more levels of branch nodes there and the more I/O is required to locate and access the appropriate leaf block node.

reverse key indexThe new B-tree index is balanced, with an even allocation of entries across the size of the leaf pages. But some values commonly used for an index are not so well behaved. Incremental values, such as ascending sequence numbers or progressively later date values, are always inserted to the right side of the index, which is the home of higher and higher values. In addition, any deletions from the index have a tendency to be skewed toward the left side as older rows are deleted. The net effect of these practices is that over time the index turns into an unbalanced B-tree structure, where the left side of the index is more meagerly populated than the leaf nodes on the right side. This unbalanced growth has to overall effect of increasing the depth of the B-tree arrangement due to the number of entries on the right side of the index. This results described here also apply to the values that are automatically decremented, except that the left side of the B-tree will end up holding more entries.

You can resolve this issue by occasionally dropping and recreating the index or rebuild index. However, you can also resolve it by using the reverse value index, which reverse the order of the value of the index. This reversal causes the index entries to be more evenly distributed over the width of the leaf nodes. For example, rather than having the values 824,825, and 826 be added to the maximum side of the index, they are translated to the value 428, 528, and 628 for storage and then translated back when the values are regained. These values are more consistently spread throughout the leaf nodes.

The generally result of the reverse index is to correct the inequality caused by repeatedly adding increasing values to a standard B-tree index. Performance point of view, reverse key index is the best solution for gaining performance of increasing number, sequence like unique values and duplicate values both.

I found the best resource to get all Oracle DBA interview Questions. Off course, there is best book available at Oracle DBA Interview Questions for real time scenario based questions, answers, and explanations.

What is Windows

October 11, 2012 Comments off

Windows is the area on the screen having the border on all four sides, to perform a specific work. Microsoft Windows executes one computer program within one window. Therefore, several programs can be executed at the same time, each in its own window. The window can be enlarged to fill the entire screen or can be sized and moved to any part of the screen.

A graphical user interface is a means by which the computer can be given commands very easily by the user. The commands, which are to be performed, are displayed on the screen in the form of pictures or icons. The user has to execute the icon to do a particular work

Clipboard is an area in the computer’s memory where MS Windows temporarily stores the copied data. The clipboard is a facility to transfer the data between two dissimilar or similar programs. The clipboard supports cut and paste or sharing between programs. When different applications are running, the data in one application can be copied or moved to another application, example a picture from ms paint can be moved to WordPad file, using the clipboard.

Object Linking and Embedding is a method wherein an object from one application can be pasted to another application and any changes in the original picture can be brought to the pasted picture also. There is a provision to change the pasted picture also by opening the application in which it was originally created.

MS Windows allows executing more than one program at a time. Each program will work in its own windows and the user can switch to any program without closing the previous program. The windows can be displayed side by side or one behind the other. This future is called as multitasking.

When the document is printed on the paper, the printout will look exactly like the document is displayed on the screen. That is, the text will be printed using the same character size, text formatting, alignment, and pictures if any included in the file will be printed at the position it is displayed on the screen.

This is the basis of Microsoft Windows. You can find out lots more tips on some forums which are having the profile. . You can get more idea from those sites about an author. Dbametrix is one of worldwide leader in remote Oracle DBA support services.

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Oracle DBA Salary

August 19, 2012 Comments off

Oracle Salary or Oracle DBA Salary

oracle dba salaryWith the common wage of a knowledgeable Oracle DBA calculating $90,000 per season and OCP regular incomes over $80,000 per season, many organizations are appealing Oracle DBA ability with salary rewards and gaining appraisal continuously.

Experienced Oracle experts are seeing the greatest wage improves in 2010.  Professional companies to has over a number of opportunities and provides at-home perform beginning at $110,000 and up to $220,000 per season for mature DBA experts, plus nice advantages such as an annually DBA vacation.

Some professional Oracle consulting organizations are providing $1,000.00 recommendation rewards for anyone who relates a knowledgeable Oracle DBA with specialized abilities in RAC, Company Intellect or Oracle Programs DBA abilities.

While the low-end of starter Oracle DBA incomes stay low, incomes are improving quickly for Oracle DBA’s with experience in handling mission-critical techniques.

Oracle DBA Salaries are among the greatest in the IT market, with Oracle DBA incomes now calculating over $100,000 per season.

Fresher Oracle DBA Salary

The excellent of your backdrop has a large impact on your Oracle DBA salary, and Oracle experts with high expertise qualification control roughly 3 times higher than age for their incomes.  For example, a 21 year-old finishing from graduation with a BS level can anticipate generating about $65,000 in wage their first season as fresher Oracle DBA.

Higher Educated DBA Salary –

Graduate students of any good university approved business educational institutions (Bachelors and Higher Education) control a wage top quality, as finish graduates of extremely aggressive institutions, distance educations, and universities.  For instance, Oracle Organization employs their software designers (at extremely aggressive salaries) from educational institutions that need effort, such as fight it out, MIT, Stanford and UT Austin, tx.  On the other hand, graduates of without any Oracle or another IT certification are not obtaining any job and become unemployed.

Oracle DBA certification Salary –

Oracle experts with innovative levels generate far more than the common.

Qualifications and Salary –

Obtaining only degree does not providing any job guarantee with any kind of salary package. If you have made investment in profession of Oracle DBA then you would gain both.

Overall, good and nice package is being gained by every Oracle DBA. Oracle salary is high for every DBA. Some great company offers nice salary to Oracle developer too.

How to be Oracle DBA –

Taking good Oracle training and DBA interview questions preparation, you would get good job easily and quickly. Job interview preparation is most important part of Oracle DBA using trick of Oracle DBA job interview questions book.

How You Should Handle a Difficult Boss?

August 6, 2012 Comments off

How You Should Handle a Difficult Boss? Are you able to tackle your reporting boss?

Do you love your job, but not necessarily your boss?  If you have a difficult boss, your first impulse may be to quit your job.  Of course, the decision to quit your job because of your boss is your decision to make, but you shouldn’t put your future or your finances in jeopardy because of someone else.  For tips on how to handle difficult bosses, you may want to continue reading on.

One of the best ways to go about dealing with a difficult boss involves having an open line of communication, as often as possible.  You may be surprised how many conflicts and problems arise from miscommunication.  What you may interpret as a mean, mad, or upset boss, many actually just be the result of miscommunication.  Even if you aren’t required to update or report to your boss, you may want to consider doing so.  This is especially easy if you and your boss work in the same establishment.

Another one of the many ways that you go about handling a difficult boss involves keeping your opinions to yourself. As much as you want to, you will want to refrain from talking badly or gossiping about your boss.  Unfortunately, many individuals, possibly just like you, do not realize who talks to who or how fast word can travel.  If you and your supervisor already have a strained relationship, you will not want to make it worse with workplace gossip.

You can also try and improve your workplace relationship with your boss by extending an olive branch. You may want to go out of your way to be polite and offer assistance.  For example, you may want to consider offering to work late or offer your assistance for a project that may have a tight deadline.  Also, something as simple as saying hello or acknowledging your boss may be enough to improve their attitude or demeanor toward you.  You need to remember that working in management can be difficult.  That is what leads many managers to have the demeanors that they have.  Many feel as if they need to be professional and demanding, all at the same time.

If you have tried all of the above mentioned approaches and are still having problems dealing with your difficult boss, you may want to consider going over your supervisor’s head.  In most cases, you will find that your supervisor has someone that they need to report to.  While this approach may be able to help you deal with a difficult boss, it is important that you use your best judgment. You do not want to go above your supervisor with small problems, such as a rushed meeting.  Issues that you may want to bring to the attention of your boss’s supervisor include sexual harassment or multiple promotion denials.

Another approach that you can take involves quitting your job.  However, as stated above, you may want to refrain from doing so.  It is advised that you do not let another person, such as your boss, ruin your opportunity to have a good job or receive funds to pay your bills and support your family. Before you make the decision to hand in your resignation, it is advised that you seriously consider your decision to quit, as well as the consequences for doing so.  If you are sure that resigning from your job is the best decision, you will want to do so in a pleasant and appropriate manner, no matter how you feel about your supervisor.

Alas!!!! You can get some basic tips of DBA Interview Questions but mainly scenario is that, without getting job, you would not getting exact experience about how to handle your reporting boss. Off course, it is very difficult to obtain Oracle DBA jobs nowadays. Oracle DBA Interview Questions  book would definitely help you to grab job easily and quickly. But, after getting job, maintaining job is very difficult too.

Oracle DBA Interview Questions

May 30, 2012 Comments off

oracle dba interview questionsHere are some Oracle DBA Interview Questions and Answers for Experienced DBA.

You can find out some useful and tricky interview questions for Oracle DBA. Generally these kind of queries are being raised during technical interview of Oracle DBA. Sometimes may be more complex questions is being asked during technical interview. All things are depending on experience of candidate as interviewee.

Q-1) Your database has a large number of active transactions, as noted by querying the v$transaction view. You attempt to place the USER_DATA tablespace in read-only mode, but your command appears to hang. What is the reason?

The tablespace is in transitional read-only mode and is waiting for existing transactions to be completed. Due to this reason, read-only command is waiting to be finished all active transactions.

Q-2) Which method is the preferred way to move big chunk of self contained data from one database to another database?

Transportable tablespace method provides the quickest way to move large amount of self contained data from one database to another database.

Q-3) How much time will be consumed of 2 TB database restored?

It depends on server hardware and backup. Normally, it takes around 1 hour to 4 hours. But if backup took using snapshot utility then it takes 5 minutes to 10 minutes.

Q-4) NLS_SORT_ORDER or NLS_COMP, Which one NLS parameter is used to control sort ordering and comparison operations?

NLS_COMP parameter has two possible values BINARY and ANSI. Setting NLS_COMP to BINARY causes sort ordering and comparisons to occur based on binary value of the variables. Setting it to ANSI causes an alphabetic or linguistics sort order precedence. Means NLS_COMP is correct.

Q-5) What will happen if the ARCH process cannot copy an archived redo log to a mandatory archive-log destination?

Oracle will continue to cycle through the other online redo log groups until it returns to the group that the ARCH process is trying to copy to the mandatory archive-log destination. If the mandatory archive log destination copy has not occurred, the database operations will suspend until the copy is successful or the DBA has intervened.

In short we can say that, The Oracle database will suspend operations when it attempts to reuse the online redo log that is waiting to be archived to the mandatory destination.

Q-6) If you drop a partition from partitioned global index, How will this operation affect the other partitions in that index?

The partition with the next highest partition range will be marked unusable, and it will need to be rebuilt.

Q-7) How to compare 2 schema objects from different databases?

We can compare using database link and minus function in our sql query. If we have TODD utility then we can compare both schemas from different databases using future of Compare schemas.

Q-8) How to recover Oracle database without Backup?

If flash recovery is enabled then we can recover database without having backup. Otherwise, we cannot recover database without backup.

Q-9)I want to restore my backup at another machine then how can I proceed?

First you need to install same Oracle version at another machine without default database. After that you need to restore backup of database and need to create parameter file using appropriate parameters with respective valid path. Create password file. If data file location is changed then you need to create control file. Just restart your database.

There are numbers of tricky and real time scenario based interview questions can be asked during Oracle Interview. You need to satisfy interviewer with appropriate and logically correct answers. If you are experienced Oracle DBA then more tricky and real time scenario based questions are being asked. I found very good and excellent book of Oracle DBA Interview Questions and Answers of Gitesh Trivedi. I bought book and surprised when I cleared 4 toughest technical interviews of MNC. This book is really great and helpful to all fresher, intermediate, and experienced DBA. This book is most popular book and so many interviewer uses this book for taking interview. Alas, great magical resource I found.

There are more sample resource of book available as following links.

http://www.kendba.com/sample-chapters/oracle-backup-recovery-interview-questions/
http://www.kendba.com/sample-chapters/oracle-sql-interview-questions/

Oracle Performance Tuning

March 14, 2012 Comments off

Oracle Performance Tuning Tips

Basic system administration is essential to resolve Oracle performance tuning issues. Otherwise, issue would be something else and you would waste your efforts in wrong investigation at database side. So many issues can impact slowness of Oracle server. If any third party application is running which is not part of Oracle database but it can consume more resources at server side. Means we cannot say every time problem of Oracle database. In various issues, Oracle database doesn’t involve in resource contention but overall server’s resource contention is impacting Oracle database performance.

Therefore, we can say that, we need some basic knowledge of system administration during examining resource contention of database level. In Windows system, you would not get different kind of utilities for server monitoring but in Linux and Unix you can various options. During server monitoring, you can exact idea of resource contention, it is either database side or operating system side. This examination is always point out the bootstrap of performance bottleneck of Oracle server.

Task manager of Windows system, would give you exact idea of different applications including Oracle instance. You would obtain disk usage, physical I/O, memory usage, paging activity from Windows Task Manager. You can analyze issue using trace files of Oracle for problem solving of performance. Windows System Event Viewer is also offering you some kind of facility to see resource contention at server side.

Thus, we can say that for troubleshooting of performance problems of Oracle databases, we need some fundamental knowledge of server. You can get more details and performance tuning tips from other resources. Every time same scenario doesn’t occur and we cannot say it would not occur. But most of the cases, problem solving becomes easy while examine system level in Oracle tuning. Oracle DBA blog would help you to obtain special tips.