Sql Server Interview Questions
Q1. WHICH TCP/IP PORT DOES SQL SERVER RUN ON? HOW Might IT BE CHANGED?
Ans: SQL Server runs on port 1433. It very well may be transformed from the Network Utility TCP/IP properties.
Q2. WHAT ARE THE DIFFERENCE BETWEEN CLUSTERED AND A NON-CLUSTERED INDEX?
A bunched list is a unique sort of file that reorders how records in the table are genuinely put away. In this way table can have just a single bunched file. The leaf hubs of a bunched record contain the information pages.
A non bunched record is an exceptional sort of file where the sensible request of the list doesn't match the actual put away request of the columns on circle. The leaf hub of a non bunched file doesn't comprise of the information pages. All things considered, the leaf hubs contain file lines.
Q3. WHAT ARE THE DIFFERENT INDEX CONFIGURATIONS A TABLE CAN HAVE?
Ans: A table can have one of the accompanying record designs:
A bunched file
A bunched file and numerous nonclustered records
A nonclustered file
Numerous nonclustered files
Q4.WHAT ARE DIFFERENT TYPES OF COLLATION SENSITIVITY?
Case responsiveness - An and a, B and b, and so forth.
Kana Sensitivity - When Japanese kana characters Hiragana and Katakana are dealt with in an unexpected way, it is called Kana delicate.
Width responsiveness - A solitary byte character (half-width) and a similar person addressed as a twofold byte character (full-width) are dealt with uniquely in contrast to it is width delicate.
Q5. WHAT IS OLTP (ONLINE TRANSACTION PROCESSING)?
Ans: In OLTP - online exchange handling frameworks social data set plan utilize the discipline of information demonstrating and for the most part observe the Codd guidelines of information standardization to guarantee outright information honesty. Utilizing these principles complex data is separated into its most straightforward designs (a table) where every one of the individual nuclear level components connect with one another and fulfill the standardization rules.
Q6. WHAT'S THE DIFFERENCE BETWEEN A PRIMARY KEY AND A UNIQUE KEY?
Ans: Both essential key and extraordinary key upholds uniqueness of the section on which they are characterized. Be that as it may, of course essential key makes a bunched file on the segment, where are special makes a nonclustered record naturally. That's what another significant distinction is, essential key doesn't permit NULLs, however interesting key permits one NULL as it were.
Q7. WHEN IS THE USE OF UPDATE_STATISTICS COMMAND?
Ans: This order is essentially utilized when a huge handling of information has happened. In the event that a lot of erasures any adjustment or Bulk Copy into the tables has happened, it needs to refresh the records to consider these changes. UPDATE_STATISTICS refreshes the lists on these tables appropriately.
Q8. WHAT IS THE DIFFERENCE BETWEEN A HAVING CLAUSE AND A WHERE CLAUSE?
Ans: They determine a quest condition for a gathering or a total. However, the thing that matters is that HAVING can be utilized exclusively with the SELECT assertion. HAVING is normally utilized in a GROUP BY condition. At the point when GROUP BY isn't utilized, HAVING acts like a WHERE proviso. Having Clause is essentially involved exclusively with the GROUP BY capability in a question though WHERE Clause is applied to each line before they are important for the GROUP BY capability in a question.
Q9. WHAT ARE THE PROPERTIES AND DIFFERENT TYPES OF SUB-QUERIES?
Properties of Sub-Query
A sub-question should be encased in the enclosure.
A sub-question should be placed in the right hand of the examination administrator, and
A sub-question can't contain an ORDER-BY provision.
An inquiry can contain more than one sub-question.
Sorts of Sub-Query
Single-line sub-inquiry, where the sub-question returns just a single column.
Different column sub-inquiry, where the sub-question returns various lines,. what's more,
Numerous segment sub-question, where the sub-inquiry returns various sections
Q10. WHAT IS SQL PROFILER?
Ans: SQL Profiler is a graphical device that permits framework executives to screen occasions in an example of Microsoft SQL Server. You can catch and save information about every occasion to a record or SQL Server table to break down later. For instance, you can screen a creation climate to see which put away strategies are hampering exhibitions by executing too leisurely.
Use SQL Profiler to screen just the occasions in which you are intrigued. Assuming follows are turning out to be excessively enormous, you can channel them in light of the data you need, so just a subset of the occasion information is gathered. Observing an excessive number of occasions adds above to the waiter and the checking system and can cause the follow document or follow table to become exceptionally huge, particularly while the observing system happens over a significant stretch of time.
Q11. WHAT ARE THE AUTHENTICATION MODES IN SQL SERVER? HOW Might IT BE CHANGED?
Ans: Windows mode and Mixed Mode - SQL and Windows. To change validation mode in SQL Server click Start, Programs, Microsoft SQL Server and snap SQL Enterprise Manager to run SQL Enterprise Manager from the Microsoft SQL Server program bunch. Select the server then from the Tools menu select SQL Server Configuration Properties, and pick the Security page.
Q12. WHICH COMMAND USING QUERY ANALYZER WILL GIVE YOU THE VERSION OF SQL SERVER AND OPERATING SYSTEM?
Ans: SELECT SERVERPROPERTY ('productversion'), SERVERPROPERTY ('productlevel'), SERVERPROPERTY ('version').
Q13.WHAT IS SQL SERVER AGENT?
Ans: SQL Server specialist assumes a significant part in the everyday undertakings of a data set director (DBA). It is in many cases neglected as one of the fundamental apparatuses for SQL Server the executives. Its motivation is to facilitate the execution of undertakings for the DBA, with its full-capability booking motor, which permits you to plan your own positions and scripts.
Q14.CAN A STORED PROCEDURE CALL ITSELF OR RECURSIVE STORED PROCEDURE? The amount LEVEL SP NESTING IS POSSIBLE?
Ans: Yes. Since Transact-SQL upholds recursion, you can compose put away methods that call themselves. Recursion can be characterized as a strategy for critical thinking wherein the arrangement is shown up at by monotonously applying it to subsets of the issue. A typical utilization of recursive rationale is to perform numeric calculations that loan themselves to tedious assessment by similar handling steps. Put away methodology are settled when one put away technique calls another or executes oversaw code by referring to a CLR schedule, type, or total. You can settle put away methodology and overseen code references up to 32 levels.
Q16. WHAT IS LOG SHIPPING?
Ans: Log transporting is the most common way of robotizing the reinforcement of data set and exchange log records on a creation SQL server, and afterward reestablishing them onto a backup server. Undertaking Editions just backings log transporting. In log delivering the conditional log document from one server is consequently refreshed into the reinforcement data set on the other server. In the event that one server comes up short, the other server will have a similar db and can be involved this as the Disaster Recovery plan. The vital component of log delivering is that it will naturally reinforcement exchange logs over the course of the day and consequently reestablish them on the backup server at characterized stretch.
Q17. NAME 3 WAYS TO GET AN ACCURATE COUNT OF THE NUMBER OF RECORDS IN A TABLE?
SELECT * FROM table1
SELECT COUNT(*) FROM table1
SELECT columns FROM sysindexes WHERE id = OBJECT_ID(table1) AND indid < 2
Q18. What's the significance here TO HAVE QUOTED_IDENTIFIER ON? WHAT ARE THE IMPLICATIONS OF HAVING IT OFF?
Ans: When SET QUOTED_IDENTIFIER is ON, identifiers can be delimited by twofold quotes, and literals should be delimited by single quotes. At the point when SET QUOTED_IDENTIFIER is OFF, identifiers can't be cited and should keep all Transact-SQL guidelines for identifiers.
Q19. WHAT IS THE DIFFERENCE BETWEEN A LOCAL AND A GLOBAL TEMPORARY TABLE?
A neighborhood impermanent table exists just for the term of an association or on the other hand, whenever characterized inside a compound explanation, as long as necessary.
A worldwide brief table remaining parts in the data set forever, however the lines exist just inside a given association. At the point when association is shut, the information in the worldwide impermanent table vanishes. Be that as it may, the table definition stays with the data set for access when information base is opened next time.
Q20. WHAT IS PRIMARY KEY?
Ans: A PRIMARY KEY requirement is a one of a kind identifier for a column inside an information base table. Each table ought to have an essential key imperative to particularly recognize each line and just a single essential key requirement can be made for each table. The essential key requirements are utilized to authorize element trustworthiness.
Q21. WHAT IS UNIQUE KEY CONSTRAINT?
Ans: A UNIQUE requirement upholds the uniqueness of the qualities in a bunch of segments, so no copy values are placed. The interesting key limitations are utilized to uphold substance uprightness as the essential key requirements.