SQL query statement for addition and subtraction of mysql date

The job needs to query the data of this month and this month for ranking. Take a closer look at the date format stored in the database, which is, in this way, I thought that the query method of the database by second would not work. I found a date addition and subtraction SQL function datediff (now, oldtime) on the Internet ). After testing, I can use the following steps to show my operation process. [

The job needs to query the data of this month and this month for ranking. Take a closer look at the database tutorial. The date format saved in the database is, in this way, I thought that the query method of the database by second would not work. I found a date addition and subtraction SQL function datediff (now, oldtime) on the Internet ). After testing, I can use the following steps to show my operation process. [

Select * from t whereDatediff (now (), senddate) <31Order by click desc limit // query the ranking of click data in a month

Select * from t whereDatediff (now (), senddate) <7Order by click desc limit // query the data of one week

Select * from t whereDatediff (now (), senddate) <= 1Order by click desc limit // locate the data of the current day

This makes it much easier to operate. The now function can be identified in the mysql tutorial. Let's look at the instance below.

Mysql> select now ();
+ --------------------- +
| Now () |
+ --------------------- +
| 22:20:46 |
+ --------------------- +

Now, is it very convenient to add or subtract the date,