SQL Quiz

Which of the following is NOT a data type in SQL Server?

• Boolean

• Int

• Char

• Float

What is the maximum number of characters for a NVARCHAR column?

• 4000

• Unlimited

• 800

• 8000

What does the acronym ACID stand for in the context of databases?

• Atomicity, Consistency, Isolation, Durability

• Accuracy, Consistency, Isolation, Durability

• Atomicity, Compatibility, Isolation, Durability

• Atomicity, Consistency, Integrity, Durability

Which of the following statements about the SQL Server Indexes are true?

• Indexes are automatically created for primary key

  constraints

• Unique indexes do not allow NULL values

• Non-clustered indexes always have smaller storage

  footprint than clustered indexes

• Clustered indexes physically reorder the data in the

  table

Which datatype would you use to store a fixed-length, Unicode string in SQL Server?

• NCHAR

• VARCHAR

• NVARCHAR

• CHAR

What type of join returns all rows from both tables, joining records where matching & adding NULLs if there's no

match?

• CROSS JOIN

• INNER JOIN

• FULL OUTER JOIN

• LEFT JOIN

In SQL Server, can a stored procedure call another stored procedure?

• No, stored procedures cannot call other stored

  procedures

• Yes, but only 1 level deep

• Yes, with unlimited nesting levels

• Yes, but limited to 3 levels of nesting

Can a view in one database reference tables in another database on the same server in SQL Server?

• Yes, but cross-database views can only be created

  by system administrators

• Yes, cross-database views on the same server are

  fully supported

• No, SQL Server does not allow cross-database view

  references even if they are on the same server

• Yes, but cross-database views on the same server

  require the use of linked servers

Which of the following statements about the performance impact of UNION and UNION ALL in SQL Server is

true?

• UNION ALL often faster, since no duplicate removal

  required

• UNION and UNION ALL same performance

• Performance depends on number of tables involved

• UNION often faster, since returns a smaller result

In SQL, what are the primary advantages of using a Common Table Expression (CTE) over a subquery?

• CTEs can be referenced multiple times within the

  same query.

• CTEs simplify complex recursive queries which is

  challenging with subqueries

• CTEs can only be used in SELECT statements

• CTEs cannot be nested within another CTE