php - now() を昨日にする方法

Question

dealend を今ではなく昨日に設定したい。このコマンドラインでそれを行う方法はありますか?

$query = mysqli_query($myConnection, "UPDATE bookdeals SET dealend='now()' WHERE id='$pid'") or die (mysqli_error($myConnection));

Answer 1

... SET dealend = now() - INTERVAL 1 DAY

Note that with the 'now()' you're using, you're not using a function called "now". You're trying to set your table field to be a string whose contents are the letters n, o, w etc.... Quotes turn things into strings and those things lose their specialty once they've been stringed.

Answer 2

MySQL DATE_SUB 関数を使用できます

... dealend=DATE_SUB(now(),INTERVAL 1 DAY) ...

MySQL 日付関数の詳細については、こちらをお読みください