GETRANGE and SETRANGE in Redis - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get a substring from a Redis string key using GETRANGE.

Redis

GETRANGE mykey [1] 4

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

A10

B0

C-1

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using a negative start index without understanding it counts from the end.

Using an index larger than the string length.

The GETRANGE command extracts a substring from the string stored at the key. The first argument after the key is the start index. Using 0 starts from the beginning.

2fill in blank

medium

Complete the code to set a substring in a Redis string key starting at offset 3 using SETRANGE.

Redis

SETRANGE mykey [1] "abc"

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

A3

B-1

C0

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using negative offsets which are invalid for SETRANGE.

Confusing the offset with the length of the substring.

The SETRANGE command overwrites part of the string stored at the key, starting at the specified offset. Offset 3 means the substring starts at the fourth character.

3fill in blank

hard

Fix the error in the GETRANGE command to correctly get characters from index 2 to 5.

Redis

GETRANGE mykey [1] 5

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

A5

B1

C3

D2

Attempts:

3 left

💡 Hint

Common Mistakes

Starting at index 1 which skips the first character.

Using the end index as the start index.

The start index should be 2 to get characters from index 2 to 5 inclusive.

4fill in blank

hard

Fill both blanks to set the substring "xyz" starting at offset 1 and then get the substring from index 0 to 3.

Redis

SETRANGE mykey [1] "xyz"
GETRANGE mykey 0 [2]

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

A1

B2

C3

D4

Attempts:

3 left

💡 Hint

Common Mistakes

Using offset 0 for SETRANGE which replaces from the first character.

Using 2 as the end index in GETRANGE which returns fewer characters.

SETRANGE uses offset 1 to start replacing at the second character. GETRANGE uses 3 to get characters from index 0 to 3 inclusive.

5fill in blank

hard

Fill all three blanks to set "123" at offset 0, then "abc" at offset 3, and finally get substring from 0 to 5.

Redis

SETRANGE mykey [1] "123"
SETRANGE mykey [2] "abc"
GETRANGE mykey 0 [3]

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

A0

B3

C5

D6

Attempts:

3 left

💡 Hint

Common Mistakes

Using offset 1 instead of 0 for the first SETRANGE.

Using 6 as the end index in GETRANGE which returns too many characters.

First SETRANGE starts at offset 0 to set "123". Second SETRANGE starts at offset 3 to set "abc" after the first three characters. GETRANGE from 0 to 5 gets the first six characters.