Talent Ghar Interview Questions and Answers

To delete duplicate records, use SQL queries with DISTINCT keyword or create a unique index on the table.

• Use SQL queries with DISTINCT keyword to select unique records and insert them into a new table

• Create a unique index on the table to prevent duplicate entries in the future

• Use DELETE statement with a subquery to remove duplicate records from the table

Yes, I am comfortable with 24x7 support as I understand the importance of continuous support in a fast-paced environment.

• I am willing to work in shifts to provide round-the-clock support

• I have experience working in a similar role with 24x7 support requirements

• I understand the importance of timely response and resolution of issues in a 24x7 support setup

Different types of joins in SQL include inner join, left join, right join, and full outer join.

• Inner join: Returns rows when there is a match in both tables.

• Left join: Returns all rows from the left table and the matched rows from the right table.

• Right join: Returns all rows from the right table and the matched rows from the left table.

• Full outer join: Returns rows when there is a match in either table.

Primary key uniquely identifies each record in a table, while a unique key ensures that all values in a column are distinct.

• Primary key is a combination of unique and not null constraints

• Primary key can only be one per table

• Unique key can have multiple per table

• Example: Primary key - employee_id, Unique key - email

Delete removes rows one by one and can be rolled back, while truncate removes all rows at once and cannot be rolled back.

• Delete is a DML command, while truncate is a DDL command.

• Delete operation is slower as it generates a lot of undo and redo logs, while truncate is faster.

• Delete can have a WHERE clause to specify which rows to delete, while truncate removes all rows in a table.

• Delete can be rolled back using ROLLBACK command, while truncate cannot be rolled back.

• Delete oper...read more