MySQL 按天分组，带有 TIMESTAMP 列

Question

I have a mysql table that has a column for "date time" in TIMESTAMP format. Is there a way to group the rows by day using that column? And in an SQL query, not grouping them in php.

Answer 1

Assuming your column is one of the Date and Time types :

SELECT ... GROUP BY DATE(`datetimecolumn`)

Answer 2

GROUP BY TO_DAYS(`datetime_column`)

Answer 3

If you mean you have a standard DATETIME column, you can group by using one of the functions described here .

For instance:

GROUP BY DATE(datetime_column);

If you actually have a TEXT or VARCHAR column (your answer doesn't specify), then you'll need to convert it to to a date first:

GROUP BY DATE(STR_TO_DATE(datetime_column));