SQL - 选择unixtimestamp作为日期

I am trying to select an unixtimestamp column from my database, as readable date time:

SELECT count(*) FROM users WHERE user_by="Admin" AND expire(FROM_UNIXTIME(unixtime),'%Y-%m-%d')='2015-10-02'

Above gives me this error:

#1305 - FUNCTION database_maindb.expire does not exist

How can I select the unixtimestamp from column expire as datetime, in the format: year-month-date?

assuming your database field is called "expire":

SELECT count(*) FROM users WHERE user_by="Admin" AND FROM_UNIXTIME(expire,'%Y-%m-%d')='2015-10-02'

see http://dev.mysql.com/doc/refman/5.1/en/date-and-time-functions.html#function_from-unixtime for details

You don't need to select is as the YMD date stamp, you could do something such as (using your tags)

$query = "SELECT * FROM `table`;";
$result = pdoObject->queryMethod($query);
$result= pdoObject->fetchAssocMethod($result);
$date = date("Y-m-d", $result['epochCol']);

I hope this helps.