SQL Server Developer Job FAQ

It is very difficult to find a very qualified database developer in the current job market. One of my colleagues once said: "SQL Development is a language, it is easy to learn, but difficult to grasp." ”

When interviewing a candidate for a SQL Server Database developer, I used a standard set of benchmark technical issues. Here are a few of the questions I think can really help to eliminate unqualified candidates. They are arranged in order from easy to difficult. When you ask questions about primary and foreign keys, the following questions are difficult, because the answer may be more difficult to explain and describe, especially in the case of an interview.

Can you give me a brief account of some of the database objects used in SQL Server 2000?

The answers you want to hear include objects such as tables, views, user-defined functions, and stored procedures, even better if they can mention objects like triggers. If the candidate can't answer the basic question, then this is not a good omen.

What is an index? What type of index is in SQL Server 2000?

Any experienced database developer should be able to easily answer this question. Some of the less experienced developers can answer the question, but there are some areas where it is unclear.

Simply put, an index is a data structure that is used to quickly access data in a database table or view. In SQL Server, they have two forms: clustered indexes and nonclustered indexes. The clustered index holds the data at the leaf level of the index. This means that regardless of which (or which) fields are in the clustered index, the fields are saved sequentially in the table. Because of this sort, each table will have only one clustered index. A nonclustered index has a row identifier at the leaf level of the index. This row identifier is a pointer to data on the disk. It allows multiple nonclustered indexes per table.

What do you mean by null?

Null (empty) This value is a very difficult thing in the database world, so there are a lot of candidates who will stumble over this issue and don't be surprised.

This value of NULL represents unknown (unknown): It does not represent "" (an empty string). Suppose you have ansi_nulls in your SQL Server database, of course, by default, and any comparison of NULL values will produce a null value. You can't compare any value to a unknown value and logically expect an answer. You must use the IS null operator.