Conditional expressions in DynamoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the attribute 'status' equals 'active' in a DynamoDB conditional expression.

DynamoDB

ConditionExpression = "status = [1]"

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

A":val"

B":active"

C"active"

D":status"

Attempts:

3 left

💡 Hint

Common Mistakes

Using the actual string 'active' without a placeholder.

Using attribute names instead of value placeholders.

In DynamoDB conditional expressions, attribute values are referenced using placeholders starting with a colon, like ':active'.

2fill in blank

medium

Complete the code to check if the attribute 'age' is greater than 30 in a DynamoDB conditional expression.

DynamoDB

ConditionExpression = "age [1] :ageVal"

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

A>

B<=

C=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

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

Using '<' or '<=' which check for less than.

The '>' operator checks if 'age' is greater than the value of ':ageVal'.

3fill in blank

hard

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

DynamoDB

ConditionExpression = "score [1] :maxScore"

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 not valid in DynamoDB expressions.

The '<=' operator correctly checks if 'score' is less than or equal to ':maxScore'.

4fill in blank

hard

Fill both blanks to check if 'status' is 'pending' and 'priority' is greater than 5 in a DynamoDB conditional expression.

DynamoDB

ConditionExpression = "status = [1] AND priority [2] :prioVal"

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

A":pending"

B<

C>

D":status"

Attempts:

3 left

💡 Hint

Common Mistakes

Using attribute names instead of value placeholders.

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

Use ':pending' as the placeholder for 'status' and '>' to check if 'priority' is greater than ':prioVal'.

5fill in blank

hard

Fill all three blanks to check if 'category' equals 'books', 'price' is less than 20, and 'inStock' is true in a DynamoDB conditional expression.

DynamoDB

ConditionExpression = "category = [1] AND price [2] :maxPrice AND inStock = [3]"

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

A":books"

B<

C:true

D":stock"

Attempts:

3 left

💡 Hint

Common Mistakes

Using actual strings instead of placeholders.

Using wrong comparison operators.

Using incorrect placeholders for boolean values.

Use ':books' as the placeholder for 'category', '<' for price comparison, and ':true' for the boolean 'inStock'.