MySQL date_format和日期范围

Question

I am trying to generate a MySQL query that would display records between a specific date range.

Catering for a predominantly British userbase I have to format dates in a day-month-year manner.

As a result, I am storing dates as follows:

$timestamp = date("d-m-Y H:i:s");

Now I am trying to run a MySQL query to return results between a set date range. Time of day isn't so much of an issue for this specific query.

I have come up with the following which doesn't seem to generate any results.

SELECT * FROM table WHERE DATE_FORMAT(`timestamp`, '%d-%m-%Y %H:%i:%s') BETWEEN '01-01-2015 00:00:00' AND '31-12-2015 23:59:00'

I have ensured that date_format contents matches the same values of php date() variable yet it still doesn't display anything!

It might be worth noting that the timestamp column is set to be a varchar(255) for type.

Any ideas how I could achieve this?

Answer 1

Choose the right percentage!. Use %m instead of %c . %m is zero-padded (as you need it, ie 01 - 12 ) whereas %c is not (ie 1 - 12 ).

See here for details.

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Update:

Sorry, the above is not true, as you store your dates as strings. I answered too quickly.

The problem is that you are comparing strings. So '14-02-2017' is before '24-12-2015'. Thus you have to convert your string into a date_time value as well:

str_to_date(`timestamp`, '%d-%m-%Y %H:%i:%s')

Then you have to compare this with the values given, converted to the type date_time:

... where str_to_date(`timestamp`, '%d-%m-%Y %H:%i:%s') 
  between str_to_date('01-01-2015 00:00:00', '%d-%m-%Y %H:%i:%s')
      and str_to_date('31-12-2015 23:59:00', '%d-%m-%Y %H:%i:%s');

However, I would strongly suggest that you store your date in DATE_TIME columns and only convert them during INSERT (with STR_TO_DATE) and SELECT (with DATE_FORMAT).

Answer 2

replace your with this one:

SELECT * FROM table WHERE DATE_FORMAT(FROM_UNIXTIME(timestamp), '%d-%m-%Y %h:%i:%s') 
BETWEEN '01-01-2015 00:00:00' AND '31-12-2015 23:59:00'