Redis does check-in statistics

Foreword

If there are only two states (yes or no) like check-in, binary state statistics can be used.bitmap conforms to binary state statistics (0,1), and takes up little space

Count check-ins in a month

Here takes user id: 1, August as an example, assuming 1, 3, 5, 7, 9 check-in

setbit sign:1:202208 1 1setbit sign:1:202208 3 1setbit sign:1:202208 5 1setbit sign:1:202208 7 1setbit sign:1:202208 9 1

Count the number of check-in days in the current month

# get signed in for 5 daysbitcount sign: 1:202208

Check if a day in the current month is checked in

# 3rd signed ingetbit sign:202208 3# No check-in on the 4thgetbit sign:202208 4

Counting consecutive check-ins

It is not suitable to use user id + month as the key for continuous check-in statistics.
Here, the specific check-in days are used as the key, and the bit position is used as the user id.
Suppose 20220801, users 1, 3, 5, 7, and 9 check in.

setbit sing:20220801 1 1setbit sing:20220801 3 1setbit sing:20220801 5 1setbit sing:20220801 7 1setbit sing:20220801 9 1

20220802, users 3, 7, 9 check in

setbit sing:20220802 3 1setbit sing:20220802 7 1setbit sing:20220802 9 1

20220803, user 5, 9 signed in

setbit sing:20220803 5 1setbit sing:20220803 9 1

Count the number of users who logged in on August 1, 2, and 3

# Put the bitwise AND results of the three dates into resultbitop and result sing:20220801 sing:20220802 sing:20220803# Statistics of consecutive check-ins# Only one user gets consecutive check-insbitcount result