EXISTS to check key existence in Redis - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the key 'user:1' exists in Redis.

Redis

EXISTS [1]

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

Auser1

B"user:1"

Cuser:1

D'user:1'

Attempts:

3 left

💡 Hint

Common Mistakes

Putting quotes around the key name.

Using an incorrect key name.

The EXISTS command requires the key name as a string without quotes in Redis CLI. Using user:1 without quotes is correct.

2fill in blank

medium

Complete the code to check if the key stored in variable 'keyName' exists.

Redis

EXISTS [1]

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

Akeyname

BkeyName

C"keyName"

D'keyName'

Attempts:

3 left

💡 Hint

Common Mistakes

Putting quotes around the variable name.

Using a different variable name.

When using a variable, do not put quotes around it. Just use the variable name.

3fill in blank

hard

Fix the error in the code to correctly check if the key 'session:123' exists.

Redis

EXISTS [1]

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

A'session:123'

B"session:123"

Csession123

Dsession:123

Attempts:

3 left

💡 Hint

Common Mistakes

Putting quotes around the key name.

Using an incorrect key name without colon.

The key name must be provided as is without quotes in Redis CLI. session:123 is correct.

4fill in blank

hard

Fill both blanks to check if the keys 'user:1' and 'user:2' exist in one command.

Redis

EXISTS [1] [2]

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

A'user:1'

B'user:2'

Cuser:1

Duser:2

Attempts:

3 left

💡 Hint

Common Mistakes

Quoting the keys.

Using variable names instead of key names.

EXISTS can check multiple keys by listing them as key names without quotes.

5fill in blank

hard

Fill all three blanks to check if keys stored in variables 'key1', 'key2', and 'key3' exist.

Redis

EXISTS [1] [2] [3]

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

Akey1

Bkey2

Ckey3

D'key3'

Attempts:

3 left

💡 Hint

Common Mistakes

Putting quotes around variable names.

Using string literals instead of variables.

When using variables, do not use quotes. Just list the variable names separated by spaces.