Test Your Microsoft SQL Server WHERE Clause Knowledge

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True / False

In SQL Server, the WHERE clause filters rows based on a condition.

True False

The WHERE clause keeps only rows for which its search condition evaluates to TRUE.

True / False

The WHERE clause should be used after GROUP BY to filter aggregate groups.

True False

HAVING filters aggregate groups. WHERE filters input rows before grouping and aggregation.

True / False

A WHERE clause can be used with SELECT, UPDATE, and DELETE statements.

True False

SELECT, UPDATE, and DELETE can all use WHERE to limit the affected rows.

True / False

The predicate column_name = NULL correctly finds NULL values in SQL Server.

True False

Use IS NULL or IS NOT NULL. Comparisons such as = NULL evaluate to UNKNOWN.

True / False

BETWEEN includes both boundary values.

True False

BETWEEN is inclusive of its lower and upper boundaries.

True / False

Without parentheses, SQL Server evaluates AND before OR in a WHERE condition.

True False

T-SQL operator precedence evaluates AND before OR. Parentheses should be used when the intended grouping may be unclear.

True / False

In a LIKE pattern, % matches zero or more characters.

True False

The percent wildcard matches any string of zero or more characters.

True / False

A column alias created in the SELECT list can always be referenced by the WHERE clause in the same query block.

True False

WHERE is logically processed before the SELECT list, so a SELECT alias is not available there in the same query block.

True / False

A NOT IN subquery that returns NULL can make the predicate UNKNOWN and unexpectedly return no rows.

True False

NULL introduces UNKNOWN in a NOT IN comparison. NOT EXISTS is often safer when the subquery can return NULL.

Q10

True / False

WHERE filters rows before aggregate functions are calculated.

True False

Rows that fail the WHERE condition are removed before grouping and aggregate calculation.

Q11

Single Choice

Which operator tests equality in a SQL Server WHERE clause?

== = EQ:=

T-SQL uses the = operator for equality comparisons.

Q12

Single Choice

What does this query return?

SQL Code

SELECT * FROM Sales WHERE Amount > 1000;

Every row in Sales Rows with Amount equal to 1000 only Rows with Amount greater than 1000Rows with Amount less than 1000

The > predicate keeps rows whose Amount is greater than 1000.

Q13

Single Choice

Which predicate correctly finds rows where EndDate has no value?

EndDate = NULL EndDate == NULL EndDate EMPTYEndDate IS NULL

IS NULL is the correct T-SQL predicate for testing a missing value.

Q14

Single Choice

Which values match WHERE Score BETWEEN 60 AND 80?

Only values greater than 60 and less than 80 Values from 60 through 80, including both Values below 60 or above 80Only 60 and 80

BETWEEN includes both endpoints and every value between them.

Q15

Single Choice

Which predicate finds names that start with A?

Name LIKE 'A%' Name LIKE '%A' Name LIKE '%A%'Name = 'A%'

A followed by % matches strings whose first character is A.

Q16

Single Choice

Which operator requires both conditions to be TRUE?

OR NOT ANDIN

AND evaluates to TRUE only when both connected conditions are TRUE.

Q17

Single Choice

Which operator checks whether a value matches any value in a list?

LIKE BETWEEN EXISTSIN

IN compares an expression with each value in a list or subquery result.

Q18

Single Choice

Which predicate tests whether a correlated subquery returns at least one row?

BETWEEN EXISTS LIKEALL

EXISTS is TRUE when its subquery returns at least one row.

Q19

Single Choice

Which keyword negates a search condition?

NOT NONE EXCEPTWITHOUT

NOT reverses the logical result of a predicate.

Q20

Single Choice

Which SQL Server function returns the number of characters in a string for use in a predicate?

LENGTH SIZE LENCOUNTCHAR

SQL Server provides LEN to return the number of characters, excluding trailing spaces.

Q21

Multiple Choice

Which statements can use a WHERE clause to limit rows?

SELECT UPDATE DELETECREATE TABLE

SELECT, UPDATE, and DELETE support row filtering with WHERE. CREATE TABLE defines a table and does not filter rows.

Q22

Multiple Choice

Which are valid comparison operators in T-SQL predicates?

= <> ><=

All four options are valid T-SQL comparison operators.

Q23

Multiple Choice

Which predicates correctly test NULL values?

Value IS NULL Value IS NOT NULL Value = NULLValue <> NULL

Use IS NULL and IS NOT NULL because ordinary comparisons with NULL evaluate to UNKNOWN.

Q24

Multiple Choice

Which are logical operators supported in a SQL Server WHERE condition?

AND OR NOTXOR

T-SQL supports AND, OR, and NOT. It has no XOR keyword for search conditions.

Q25

Multiple Choice

Which wildcards can be used by SQL Server LIKE patterns?

% for zero or more characters _ for one character [A-Z] for a character range* for zero or more characters

SQL Server LIKE supports %, _, and bracket expressions. The asterisk is not the LIKE wildcard.

Q26

Multiple Choice

Which predicates are generally able to seek directly on a suitable index?

CustomerID = 100 OrderDate >= '2026-01-01' YEAR(OrderDate) = 2026Name LIKE '%son'

Direct comparisons on indexed columns are generally searchable. Wrapping a column in a function or using a leading wildcard commonly prevents a direct seek.

Q27

Multiple Choice

Which are valid ways to use a subquery in a WHERE clause?

DepartmentID IN (SELECT DepartmentID FROM Departments) EXISTS (SELECT 1 FROM Orders WHERE Orders.CustomerID = Customers.CustomerID) Salary > (SELECT AVG(Salary) FROM Employees)WHERE ORDER BY (SELECT DepartmentID FROM Departments)

IN, EXISTS, and scalar comparisons can use subqueries. WHERE ORDER BY is not valid syntax.

Q28

Multiple Choice

Which conditions select active rows whose EndDate is NULL?

Status = 'Active' AND EndDate IS NULL EndDate IS NULL AND Status = 'Active' Status = 'Active' OR EndDate IS NULLStatus = 'Active' AND EndDate = NULL

The first two predicates are logically equivalent. OR is broader, and = NULL is not a valid NULL test.

Q29

Multiple Choice

Which predicates select values outside the inclusive range 10 through 20?

Value < 10 OR Value > 20 Value NOT BETWEEN 10 AND 20 Value < 10 AND Value > 20Value BETWEEN 10 AND 20

Outside an inclusive range means less than the lower bound or greater than the upper bound, which is also expressed by NOT BETWEEN.

Q30

Multiple Choice

Which predicates require an active row to be in either the West or East region?

Status = 'Active' AND (Region = 'West' OR Region = 'East') Status = 'Active' AND Region IN ('West', 'East') Status = 'Active' OR Region IN ('West', 'East')(Status = 'Active' AND Region = 'West') OR Region = 'East'

The first two predicates require both active status and one of the two regions. The other predicates can include rows that are not active.

Microsoft SQL Server Database Quiz Questions