Redis uses sorted set to cache latest comments

Foreword

sorted set is an ordered set.The attribute of weight is provided, and data can be obtained according to the weight.

implemented

Assuming that there are reviews 11, 22, 33, 44, 55 for product A now, the weights are accumulated from 1 (+1) according to the order of reviews.

zadd a_comments 1 11zadd a_comments 2 22zadd a_comments 3 33zadd a_comments 4 44zadd a_comments 5 55

A new comment 66 was generated at this time.Determine the weight of comment 66 (total + 1)

 # Get the total number of 5 and determine the weight of 6zcard a_comments# add to rediszadd a_comments 6 66

View the latest comments, 2 records per page.

# Get the current amountzcard a_comments# First page 55,66zrangebyscore a_comments 5 6# 2nd page 33,44zrangebyscore a_comments 3 4# 3rd page 11,22zrangebyscore a_comments 1 2