Composite index requirements in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a composite index for fields 'age' and 'score'.

Firebase

firestore.indexes().create({fields: [{fieldPath: 'age'}, {fieldPath: '[1]'}]})

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

Alocation

Bname

Cdate

Dscore

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing a field not involved in the composite index like 'name' or 'location'.

The composite index must include both 'age' and 'score' fields to support queries filtering or ordering by these fields.

2fill in blank

medium

Complete the code to specify the direction of the composite index on 'age' as ascending.

Firebase

firestore.indexes().create({fields: [{fieldPath: 'age', [1]: 'ASCENDING'}, {fieldPath: 'score', order: 'DESCENDING'}]})

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

Aorder

Bmode

Csort

Ddirection

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'direction' or 'sort' instead of 'order' causes errors.

The correct property to specify the sort order in Firestore composite indexes is 'order'.

3fill in blank

hard

Fix the error in the composite index definition by completing the missing field name.

Firebase

firestore.indexes().create({fields: [{fieldPath: 'age', order: 'ASCENDING'}, {fieldPath: '[1]', order: 'DESCENDING'}]})

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

Ascore

Bage

Cname

Dtimestamp

Attempts:

3 left

💡 Hint

Common Mistakes

Repeating 'age' or using unrelated fields like 'name' or 'timestamp'.

The composite index must include 'score' as the second field to match the query requirements.

4fill in blank

hard

Fill both blanks to create a composite index with 'city' ascending and 'population' descending.

Firebase

firestore.indexes().create({fields: [{fieldPath: '[1]', order: 'ASCENDING'}, {fieldPath: '[2]', order: 'DESCENDING'}]})

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

Acity

Bpopulation

Cage

Dscore

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the fields or using unrelated fields like 'age' or 'score'.

The composite index must have 'city' with ascending order and 'population' with descending order to support queries filtering or ordering by these fields.

5fill in blank

hard

Fill all three blanks to define a composite index with 'country' ascending, 'state' ascending, and 'city' descending.

Firebase

firestore.indexes().create({fields: [{fieldPath: '[1]', order: 'ASCENDING'}, {fieldPath: '[2]', order: 'ASCENDING'}, {fieldPath: '[3]', order: 'DESCENDING'}]})

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

Acountry

Bstate

Ccity

Dpopulation

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'population' instead of 'city' for the descending field.

This composite index supports queries filtering or ordering by 'country' and 'state' ascending, and 'city' descending.