In and not-in queries in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to query documents where the field 'status' is in a list of values.

Firebase

db.collection('orders').where('status', '[1]', ['pending', 'shipped']).get()

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

Anot-in

Bin

C==

Darray-contains

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'array-contains' which checks if an array field contains a value, not if a field matches any value in a list.

Using '==' which only checks for equality with a single value.

The 'in' operator allows querying documents where the field matches any value in the given list.

2fill in blank

medium

Complete the code to query documents where the field 'category' is not in a list of values.

Firebase

db.collection('products').where('category', '[1]', ['electronics', 'furniture']).get()

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

A!=

Barray-contains-any

Cin

Dnot-in

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' which only compares to a single value, not a list.

Using 'in' which includes documents with matching values instead of excluding them.

The 'not-in' operator filters documents where the field's value is not in the specified list.

3fill in blank

hard

Fix the error in the query to find documents where 'tags' array contains any of the given values.

Firebase

db.collection('posts').where('tags', '[1]', ['news', 'updates']).get()

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

Aarray-contains-any

Bin

Carray-contains

Dnot-in

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'in' which checks a field's value against a list, not array contents.

Using 'array-contains' which only checks for a single value.

'array-contains-any' checks if the array field contains any of the specified values.

4fill in blank

hard

Fill both blanks to query documents where 'status' is in a list and 'priority' is not in another list.

Firebase

db.collection('tasks').where('status', '[1]', ['open', 'in-progress']).where('priority', '[2]', ['low', 'medium']).get()

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

Ain

Barray-contains

Cnot-in

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' which only compares single values.

Mixing up 'in' and 'not-in' operators.

Use 'in' to include documents with matching 'status' values and 'not-in' to exclude documents with certain 'priority' values.

5fill in blank

hard

Fill all three blanks to query documents where 'category' is in a list, 'tags' array contains any value from a list, and 'status' is not in another list.

Firebase

db.collection('items').where('category', '[1]', ['books', 'games']).where('tags', '[2]', ['bestseller', 'new']).where('status', '[3]', ['archived', 'deleted']).get()

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

Ain

Barray-contains-any

Cnot-in

Darray-contains

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'array-contains' instead of 'array-contains-any' for multiple values.

Using 'in' instead of 'not-in' to exclude values.

Use 'in' for matching 'category', 'array-contains-any' for matching any tag, and 'not-in' to exclude certain statuses.