Frequently Asked Questions in SQL

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1. What is the full form of SQL?

2. What is the RDBMS?

3. Can you list some of RDBMS databases?

4. What are the NOSQL databases?

5. What is the main difference between MS SQL Server and Oracle database?

6. What is the PL/SQL?

7. What is the T-SQL?

8. Does SQL program execute on any database system? Yes or no?

9. What are the Hardware requirements to install MS SQL Server?

10. What are the Software requirements to install MS SQL Server?

11. Can we install MS SQL Server in Linux?

12. What is the usage of MS SQL Server and SSMS software's?

13. What is the server name or instance name?

14. What do you mean by server down or DB service down?

15. How to start the database service?

16. How to restart/stop the database service?

17. How you will connect to the database from a client component?

18. What are the client components you have used to connect to MS SQL Server and Oracle databases?

19. What are the reasons to unable to connect to the SQL Server databases?

20. What is he meaning of the error message "A network-related or instance-specific error occurred while establishing a connection to SQL Server........"?

1. How to create the database by using GUI?

2. How to drop the drop the database by using GUI?

3. What the recommendations to keep the database name?

4. What the options to check before we drop the databases either by using GUI or by using SQL query?

5. What are the reasons for unable to create the databases in MS SQL Server?

6. What are the reasons for unable to drop the databases in MS SQL Server?

7. How many maximum databases can be created in MS SQL Server?

8. What are the identifiers in SQL?

9. What are the single line and multi-line comments in SQL?

1. What are the database objects in SQL?
2. What is the purpose of a table in a database?
3. What is the meaning of column and row/record in a table?
4. What are all the data types in SQL?
5. What is the usage of INT data type in SQL?
6. What is the usage of DECIMAL data type in SQL?
7. What is the usage of FLOAT data type in SQL?
8. What is the usage of CHAR data type in SQL?
9. What is the usage of VARCHAR data type in SQL?
10. What are the differences between INT and Decimal?
11. What are the differences between FLOAT and Decimal data types?
12. What are the differences between VARCHAR and CHAR data types?
13. What is the best data type to store a names of persons? and why?
14. What is the best data type to store the pancard of persons? and why?
15. What is the best data type to store the salary of employees? and why?
16. What is the best data type to store the percentage of students? and why?
17. What is the best data type to store Date of Birth of persons? and why?
18. What is the best data type to store the journey date and time? and why?
19. What is the meaning of variable length column and fixed length column?
20. What is the best data type for variable length columns?
21. What is the best data type for fixed length columns?
22. What are DDL commands? And explain the usage of each and every DDL commands?
23. What are DML commands? And explain the usage of each and every DML commands?
24. What are TCL commands? And explain the usage of each and every TCL commands?
25. What are DCL commands? And explain the usage of each and every DCL commands?
26. What are DRL commands? And explain the usage of each and every DRL commands?
27. What is the usage of TRUNCATE command?
28. What is main different between ALTER and UPDATE commands?
29. What is main different between DROP and DELETE commands?
30. What is the purpose of ALTER command in SQL? Can you provide some examples when you use ALTER command?
31. What is the usage of INSERT command in SQL?
32. What are the basic rules to follow while storing data into a table?
33. What is the default format of a date value in SQL?
34. What will happen if I don't specify the date in proper format while storing it into a table?
35. What is the meaning of NULL in a row/record?
36. Can we keep NULL in a single quote while inserting it into a column whose data type is VARCHAR?
37. Can we keep NULL in a single quote while inserting it into a column whose data type is CHAR?
38. Can we keep NULL in a single quote while inserting it into a column whose data type is INT?
39. Can we keep NULL in a single quote while inserting it into a column whose data type is DATE?
40. Can we keep NULL in a single quote while inserting it into a column whose data type is FLOAT?
41. I would like to insert a blank in place of a vlaue in a record. How do you insert that blank?
42. What will happen if I try to insert number 0 into a name column whose data type if VARCHAR?
43. What will happen if I try to insert number 0 into a name column whose data type if CHAR?
44. What will happen if I try to insert number 0 into a name column whose data type if DATE?