Database Administrator (DBA)

A DBA is a Database Administrator, and this is the most common job that you find a database specialist doing. There are Development DBAs and Production DBAs.

A Development DBA usually works closely with a team of developers and gets more involved in design decisions, giving advice on performance and writing good SQL.

That can be satisfying at a human level because you are part of a team and you share the satisfaction of the teams accomplishments.

A Production DBA (on the other hand) is responsible for maintaining Databases within an organization, so it is a very difficult and demanding job. He or she, often gets involved when all the design decisions have been made, and has simply to keep things up and running.

Therefore, of course, it is also a rewarding job, both financially and in terms of job satisfaction. But it is a more "lonely" job than being a Development DBA.

You take this as a trick question and explain it that way. Never in my database carrier have I distinguished between "development" and "production." Just ask your development staff or VP of engineering how much time and money is lost if development systems are down. Explain to the interviewer that both systems are equally important to the operation of the company and both should be considered as production systems because there are people relying on them and money is lost if either one of them is down. Ok you may be saying, and I know you are, that we lose more money if the production system is down. Ok, convey that to the interviewer and you won't get anyone to disagree with you unless your company sells software or there are million dollar deals on the table that are expecting the next release of your product or service.

This is a loaded question and almost begs for you to answer it with "What DBA activities do you LIKE to do on a daily basis?." And that is how I would answer this question. Again, do not get caught up in the "typical" day-to-day operational issues of database administration. Sure, you can talk about the index you rebuilt, the monitoring of system and session waits that were occurring, or the space you added to a data file, these are all good and great and you should convey that you understand the day-to-day operational issues. What you should also throw into this answer are the meetings that you attend to provide direction in the database arena, the people that you meet and talk with daily to answer adhoc questions about database use, the modeling of business needs within the database, and the extra time you spend early in the morning or late at night to get the job done. Just because the question stipulates "today" do not take "today" to mean "today." Make sure you wrap up a few good days into "today" and talk about them. This question also begs you to ask the question of "What typical DBA activities are performed day to day within X Corporation?"

Answer1

The order of the clauses in a query syntax using a GROUP BY clause is as follows:

select …where..group by…having…order by…

Where filters, group by arranges into groups, having applies based on group by clause. Having is applied with group by clause.

Answer2

In SQL Server, procedures and functions can return values. (In Oracle, procedures cannot directly return a value).

The major difference with a function is that it can be used in a value assignment. Such as:

–system function

Declare @mydate datetime

Set @mydate = getdate()

–user function (where the user has already coded the function)

Declare @My_area

Set @My_area = dbo.fn_getMy_area(15,20)

Answer3

1.”where” is used to filter records returned by “Select”

2.”where” appears before group by clause

3.In “where” we cannot use aggregate functions like where count(*) >2 etc

4.”having” appears after group by clause

5.”having” is used to filter records returned by “Group by”<

6.In”Having” we can use aggregate functions like where count(*) >2 etc there are two more