php的mysql模糊查詢，可以允許空值（空值則查詢全部），具體代碼如下：
$sql = "SELECT * FROM user WHERE name LIKE '%".$name."%' AND age LIKE '%".$age."%' AND sex LIKE '%".$sex."%' ORDER BY id ASC
php的mysql模糊查詢，可以允許空值（空值則查詢全部），具體代碼如下：
$sql = "SELECT * FROM user WHERE name LIKE '%".$name."%' AND age LIKE '%".$age."%' AND sex LIKE '%".$sex."%' ORDER BY id ASC
![SQL語言基礎：常用的資料查詢語句[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)