XRANGE and XREVRANGE in Redis - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get all entries from the stream 'mystream' starting from the beginning.

Redis

XRANGE mystream [1] +

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

A0

B-

C1

D$

Attempts:

3 left

💡 Hint

Common Mistakes

Using '0' instead of '-' as the start ID.

Using '$' which means the latest entry, not the start.

The XRANGE command requires a start and end ID. Using '-' as the start means from the earliest entry.

2fill in blank

medium

Complete the code to get the last 5 entries from the stream 'mystream' in reverse order.

Redis

XREVRANGE mystream + [1] COUNT 5

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

A-

B0

C1

D$

Attempts:

3 left

💡 Hint

Common Mistakes

Using '0' which is not a valid stream ID.

Using '$' which is the latest entry, not the earliest.

In XREVRANGE, '+' is the latest entry and '-' is the earliest. To get last 5 entries, range from '+' to '-'.

3fill in blank

hard

Fix the error in the command to get entries from 'mystream' starting at ID '1609459200000-0'.

Redis

XRANGE mystream [1] +

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

A'1609459200000-0'

B1609459200000_0

C1609459200000-0

D1609459200000

Attempts:

3 left

💡 Hint

Common Mistakes

Adding quotes around the ID.

Replacing dash with underscore.

Using incomplete ID without sequence number.

The stream ID must be a string without quotes and with a dash '-' separating timestamp and sequence number.

4fill in blank

hard

Fill both blanks to get entries from 'mystream' between IDs '1609459200000-0' and '1609459300000-0'.

Redis

XRANGE mystream [1] [2]

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

A1609459200000-0

B1609459300000-0

C-

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping start and end IDs.

Using '-' or '+' instead of actual IDs.

XRANGE requires start and end IDs. Use the given IDs as start and end to get entries in that range.

5fill in blank

hard

Fill all three blanks to get the last 3 entries from 'mystream' in reverse order starting from the latest entry.

Redis

XREVRANGE mystream [1] [2] COUNT [3]

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

A+

B-

C3

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong start or end IDs.

Using COUNT larger than needed.

To get last 3 entries in reverse, start from '+' (latest) to '-' (earliest) with COUNT 3.