LPUSH and RPUSH for insertion in Redis - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the LPUSH command do in Redis?

LPUSH inserts one or more values at the beginning (left) of a list stored at a given key.

beginner

How does RPUSH differ from LPUSH in Redis?

RPUSH inserts one or more values at the end (right) of a list, while LPUSH inserts at the beginning (left).

intermediate

If you run LPUSH mylist "a" "b" "c", what will be the order of elements in the list?

The list will be ["c", "b", "a"] because LPUSH inserts each new element at the front, so the last value ends up first.

beginner

What happens if the key does not exist when you use LPUSH or RPUSH?

Redis creates a new list with the given values if the key does not exist.

beginner

Can LPUSH and RPUSH be used to insert multiple values at once?

Yes, both commands accept multiple values and insert them in the order given.

What does RPUSH do in Redis?

A Inserts values at the end of a list

B Deletes values from a list

C Inserts values at the beginning of a list

D Creates a new key without values

RPUSH adds one or more values to the end (right side) of a list.

If you run LPUSH mylist "x" "y", what is the order of elements?

A Empty list

B ["x", "y"]

C ["x"]

D ["y", "x"]

LPUSH inserts each value at the front, so the last value ends up first.

What happens if the list key does not exist when using RPUSH?

A Returns an error

B Creates a new list with the values

C Does nothing

D Deletes the key

Redis creates a new list with the given values if the key does not exist.

Which command inserts values at the start of a list?

A LPUSH

B RPUSH

C LPOP

D RPOP

LPUSH inserts values at the beginning (left) of the list.

Can LPUSH and RPUSH insert multiple values at once?

A Only RPUSH can

B No

C Yes

D Only LPUSH can

Both LPUSH and RPUSH accept multiple values and insert them in order.

Explain how LPUSH and RPUSH work for inserting elements into a Redis list.

Think about left and right ends of a list.

Describe the order of elements after using LPUSH with multiple values.

Imagine stacking plates on top.