简化:
$q = mysql_query("SELECT * FROM mytable ORDER BY category") or die(mysql_error());
while($row = mysql_fetch_array($q)) {
$cat = $row['category'];
echo $cat."<br />";
}
mytable
持有苹果、香蕉、柑橘
我希望结果以特定顺序显示,例如香蕉、苹果、柑橘。
如何进行查询?
取自http://dev.mysql.com/doc/refman/5.0/en/sorting-rows.html的回复
“如果您想明确指定返回“order by”的顺序,例如,如果您有一个优先级字段,其值为“低”、“高”或“中”......请执行以下操作:
select * from tablename order by priority='High' DESC, priority='Medium' DESC, priority='Low" DESC;"
对于您的情况,这将是:
$q = mysql_query("SELECT * FROM mytable ORDER BY category='Banana' DESC, category='Apple' DESC, category='Citrus' DESC") or die(mysql_error());
while($row = mysql_fetch_array($q)) {
$cat = $row['category'];
echo $cat."<br />";
}
您可以使用order by field(...)
:
SELECT * FROM mytable ORDER BY FIELD(category, 'Banana', 'Apple', 'Citrus');
http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_field - FIELD() 函数的手册。