Casting DATETIME to DATE in MySQL
In MySQL, grouping entries by date can be challenging when using a DATETIME field instead of a dedicated DATE field. To address this, you can utilize casting to convert DATETIME values to DATE.
Issue:
Your initial query attempts to group entries by follow_date using the incorrect casting syntax:
select * from follow_queue group by follow_date cast follow_date as date
This casting attempt will fail.
Solution:
To successfully cast DATETIME to DATE, use the DATE() function:
select * from follow_queue group by DATE(follow_date)
The DATE() function extracts only the date portion from the DATETIME value, discarding the time information. This allows you to group the entries based on their dates, effectively resolving the issue.
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