我有一个mysql表,如下所示:
id - year - value
-----------------
1 - 2004 - 10
2 - 2005 - 15
3 - 2006 - 8
4 - 2006 - 14
5 - 2007 - 20
6 - 2008 - 25
我需要能够从mysql中获取这个数组,并将两个2006值相加。我该怎么做?
您是否特别希望PHP执行此操作
MySQL可以计算:SELECT year, SUM(value) as value FROM table GROUP BY year
如果你真的想在php中完成(这个脚本适用于所有年份):
$rs = mysql_query("SELECT * FROM table");
while ($row = mysql_fetch_assoc($rs)){
$value[$row['year']] += $row['value'];
}
(强制引用:小心上面代码中的错误;我只证明了它是正确的,没有尝试过。-Donald Knuth)
$query = "SELECT t.year,
SUM(t.value) AS sumValue
FROM table t
GROUP BY t.year";
$result = mysql_query($query) or die(mysql_error());
// Print out result
while($row = mysql_fetch_array($result))
{
echo $row['year']. " = ". $row['sumValue'];
echo "<br />";
}
按年份从_your_table组中选择年份,SUM(值)作为值
针对您的具体情况:
$sql = "SELECT year, SUM( value ) AS total FROM table_name WHERE year = 2006";
$query = mysql_query($sql);
$result = mysql_fetch_array($query);
echo $result['total']; // 22