我有一个包含以下格式数据的表
region gender age_group population
Dallas M 1 200
Dallas F 1 500
NY M 1 320
NY F 1 310
Dallas M 2 300
Dallas F 2 600
NY M 2 400
NY F 2 800
我正在寻找以下列格式输出数据的最佳查询
region/age_group 1 2
Gender M F M F
Dallas 200 500 300 600
NY 320 310 400 800
我的查询只返回顶部列和区域。不确定如何将顶部柱子细分为上面出现的性别
SELECT distinct (region), a.group_one, b.group_two
FROM city_populations c
LEFT JOIN city_populations AS a ON a.age_group=1 AND c.age_group=a.age_group
LEFT JOIN city_populations AS b ON b.age_group=2 AND c.age_group=a.age_group
答案 0 :(得分:1)
//首先我从数据库中获取了所有数据
$result = mysql_query("select * from test2")or die(mysql_error());
$regions = array();
$age_groups = array();
while($det = mysql_fetch_array($result)){
if(!in_array($det['region'], $regions)){
$regions[] = $det['region'];
}
if(!in_array($det['age_group'], $age_groups)){
$age_groups[] = $det['age_group'];
}
$rows[] = $det;
}
//然后在php中处理以显示您想要的
echo "<table>";
echo "<tr><td>Age group</td>";
foreach($age_groups as $keyAG => $valueAG){
echo "<td colspan='2'>$valueAG</td>";
}
echo "</tr>";
echo "<tr><td>Gender</td>";
foreach($age_groups as $keyAG => $valueAG){
echo "<td>M</td>";
echo "<td>F</td>";
}
echo "</tr>";
foreach($regions as $keyR => $valueR){
echo "<tr>";
echo "<td>".$valueR."</td>";
foreach($age_groups as $keyAG => $valueAG){
foreach($rows as $keyROWS => $valueROWS){
if($valueROWS['region'] == $valueR && $valueROWS['age_group'] == $valueAG){
if($valueROWS['gender'] == 'M'){
echo "<td>".$valueROWS['population']."</td>";
}
elseif($valueROWS['gender'] == 'F'){
echo "<td>".$valueROWS['population']."</td>";
}
}
}
$data[$valueR][$valueAG] = array($maleValue, $femaleValue);
}
echo "</tr>";
}
echo "</table>";
注意:强烈建议使用mysqli_ *而不是mysql。