MySQLのDATETIME型のフォーマット
Y-m-d H:i:s
The DATETIME type is used for values that contain both date and time parts. MySQL retrieves and displays DATETIME values in 'YYYY-MM-DD HH:MM:SS' format. The supported range is '1000-01-01 00:00:00' to '9999-12-31 23:59:59'. CarbonだとtoDateTimeString()でこれに変換できる 関連
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