Top 50 SQL Server Interview Questions and Answers 2022

When the index is created with WHERE clause, then it is called Filtered Index. SQL injection is an attack by malicious users in which malicious code can be inserted into strings that can be passed to an instance of SQL server for parsing and execution. All statements have to checked for vulnerabilities as it executes all syntactically valid queries that it receives. XML data type is used to store XML documents in the SQL Server database. Columns and variables are created and store XML instances in the database. RAISEERROR is the command used to generate and initiates error processing for a given session. Those user defined messages are stored in sys.messages table.

Cursors’ performance is affected when large volumes of data are present. The volume of data, type of information stored, and data to be accessed must be checked. When a system is being upgraded, the present data should be analyzed, and the methods of accessing data should be checked to help understand problem design. Keeping the information about data is necessary when using a new system. Answered most of the Administrative questions but did 70-30% with development answers. We need a windows cluster configuration for availability groups whereas replication does not have any dependency on the windows cluster feature.

Worried about failing SQL Interviews?

SQL Server supports Windows Authentication and mixed-mode. Mixed-mode allows you to use both Windows Authentication and SQL Server Authentication to log into your SQL Server. It’s important to note that if you use Windows Authentication, you will not be able to log how to become a sql server dba in. One important thing to note here is that SQL Server can only truncate up to the oldest open transaction. Therefore, if you are not seeing the expected relief from a checkpoint, it could very well be that someone forgot to commit or rollback their transaction.

Hotfixes are small software patches that are applied to live systems. A hotfix is a single, cumulative package that includes one or more files used to address a problem in a software product. They provide the enterprise view of your backup and recovery environment. Value type and reference type may be similar regarding declaration syntax and usage, but their semantics are distinct. Value type and reference type differ with the memory area, where it stored. There is no difference between primary key and unique key but, a unique key will allow single NULL, but in the primary key, no NULL is accepted. The session object is used to maintain the session of each user.

Can we replicate SQL Server data to other RDBMS systems like Oracle?

In RDBMSs, all the data is stored in tables with each table consisting of rows and columns. The following is an example of a SQL query, CREATE DATABASE. It is a collection of schemas, tables, procedures, code functions, and other objects. Various query languages are used to access and manipulate data. In SQL Server, a table is an object that stores data in a tabular form. Top 10 Questions to Ask a Senior SQL Server DBA – if you’re hiring a database administrator, here’s ten questions to ask along with the types of answers you should expect to hear.