Multi-key operations in cluster in Redis - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the values of multiple keys in a Redis cluster.

Redis

MGET [1]

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

Akey1,key2,key3

B[key1 key2 key3]

C"key1" "key2" "key3"

D"key1 key2 key3"

Attempts:

3 left

💡 Hint

Common Mistakes

Passing all keys as one string separated by spaces or commas.

Using brackets or commas which Redis does not accept.

The MGET command requires each key as a separate argument, so you must provide each key as a separate string.

2fill in blank

medium

Complete the code to set multiple keys with their values atomically using a Redis cluster.

Redis

MSET [1]

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

A"key1" "value1" "key2" "value2"

B"key1:value1 key2:value2"

Ckey1=value1 key2=value2

D[key1 value1 key2 value2]

Attempts:

3 left

💡 Hint

Common Mistakes

Combining keys and values into one string.

Using brackets or commas which Redis does not accept.

The MSET command requires pairs of keys and values as separate arguments, each as a string.

3fill in blank

hard

Fix the error in the command to delete multiple keys in a Redis cluster.

Redis

DEL [1]

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

A"key1" "key2" "key3"

B"key1 key2 key3"

Ckey1,key2,key3

D[key1 key2 key3]

Attempts:

3 left

💡 Hint

Common Mistakes

Passing all keys as one string.

Using commas or brackets which Redis does not accept.

The DEL command requires each key as a separate argument, so you must provide each key separately in quotes.

4fill in blank

hard

Fill both blanks to correctly perform a multi-key atomic increment operation in Redis cluster using Lua script.

Redis

EVAL "return redis.call('INCRBY', [1], [2])" 0

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

A'key1'

B'key2'

C5

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong key names or missing quotes.

Passing increment as a string instead of number or vice versa.

The Lua script calls INCRBY on the key 'key1' with increment 5. Both must be strings or numbers as required.

5fill in blank

hard

Fill all three blanks to create a Redis Lua script that atomically sets a key only if it does not exist and returns the new value.

Redis

EVAL "if redis.call('SETNX', [1], [2]) == 1 then return redis.call('GET', [3]) else return nil end" 0

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

A'mykey'

B'100'

D'otherkey'

Attempts:

3 left

💡 Hint

Common Mistakes

Using different keys in SETNX and GET calls.

Passing values without quotes.

The script sets 'mykey' to '100' if it does not exist, then returns the value of 'mykey'. The same key must be used consistently.