Filter expressions in DynamoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to filter items where the attribute 'status' equals 'active'.

DynamoDB

FilterExpression = "status = [1]"

Drag options to blanks, or click blank then click option'

A":active_status_val"

B":active_val"

C":active_status"

D":active"

Attempts:

3 left

💡 Hint

Common Mistakes

Using attribute names instead of placeholders.

Forgetting the colon before the placeholder.

The filter expression uses a placeholder for the value. Here, ':active' is the correct placeholder for the value 'active'.

2fill in blank

medium

Complete the code to filter items where the attribute 'age' is greater than 25.

DynamoDB

FilterExpression = "age [1] :age_val"

Drag options to blanks, or click blank then click option'

A>

B<

C=

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>'.

Using '=' which checks for equality, not greater than.

The filter expression uses '>' to check if 'age' is greater than 25.

3fill in blank

hard

Fix the error in the filter expression to check if 'score' is less than or equal to 100.

DynamoDB

FilterExpression = "score [1] :max_score"

Drag options to blanks, or click blank then click option'

A<=

B<

C>=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' which excludes equality.

Using '==' which is invalid in DynamoDB filter expressions.

The correct operator for 'less than or equal to' is '<='.

4fill in blank

hard

Fill both blanks to filter items where 'category' equals 'books' and 'price' is less than 20.

DynamoDB

FilterExpression = "category = [1] AND price [2] :max_price"

Drag options to blanks, or click blank then click option'

A:books

B>

C<

D:books_val

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' instead of '<' for price comparison.

Using incorrect placeholder names.

The placeholder ':books' is used for the category value, and '<' is used to check if price is less than max_price.

5fill in blank

hard

Fill all three blanks to filter items where 'status' equals 'pending', 'priority' is greater than 3, and 'assigned' attribute exists.

DynamoDB

FilterExpression = "status = [1] AND priority [2] :min_priority AND attribute_exists([3])"

Drag options to blanks, or click blank then click option'

A:pending

B>

Cassigned

D:pending_val

Attempts:

3 left

💡 Hint

Common Mistakes

Using attribute names as placeholders.

Using '=' instead of '>' for priority comparison.

Not using attribute_exists() correctly.

Use ':pending' as placeholder for status, '>' for priority comparison, and 'assigned' as the attribute name to check existence.