Php website homepage image clicks statistics, how to solve

On the home page of the php website, the page displays statistics on the number of clicks on the images, and then writes the statistical results of the previous day (I want to use the early morning as the basis) to the database every day. Now I have two questions: 1. how can we determine that the clicks on images are from the previous day, that is, how to distinguish between today and yesterday? 2. considering that there are many pictures on the home page of the website, if each picture is written to the database, statistics on the number of clicks on the home page of the php website
The picture counts the clicks and writes the previous day (I want to use the early morning as the basis) to the database every day.
Now I have two questions:
1. how to determine the number of clicks on images from the previous day, that is, how to distinguish between today and yesterday;
2. considering that there are a lot of pictures on the homepage of the website, if each picture is written to the database after clicking it, the database is under too much pressure, so I don't know if there are any other methods that are more labor-saving. ask for advice...

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Obtain the timestamp. The difference is today or yesterday.
You can write the daily count in a txt file and save it to the database after one day or the next day. Otherwise, it will be slow to access the database once each click.
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Does it make sense ?? In theory, if you want to implement it, you don't need to manually delete it. The program can implement it. The idea is as follows: if the image is not clicked once, 1 is added to the corresponding field of the database, in this way, will the clicks of images in a day be reduced ?? Of course, there will be a problem that cannot distinguish "today", "Yesterday", and "tomorrow", but this is a good solution, that is, before increasing the clicks DayThe date (as of "day") is saved to another field in the database, and then the date of this field is determined to be consistent with the date of the day. if it is consistent, continue to accumulate. if not, if it is changed to 0, it is accumulating. isn't it done ?? However, daily statistics do not seem to make much sense .......