[英]Passing json data from PHP to javascript - Google Pie Chart
[英]SQL query to take avg of column data into JSON for google pie chart in PHP
I need to create a SQL query and the PHP code to enter this data into JSON format for a pie chart using Google Charts API.
+--------+---------+---------+---------+
| City | P1 | P10 | P25 |
+--------+---------+---------+---------+
|Dubai | 45| 135| 136|
|SanDiego| 23| 34| 45|
|SanFran | 37| 39| 28|
+--------+---------+---------+---------+
這是我已經嘗試過的查詢:
<?php
$rows2 = array();
$table2 = array();
$query2 = 'SELECT AVG(`P1`) AS avg_p1, AVG(`P10`) AS avg_p10, AVG(`P25`) (SELECT `P1`, `P10`, `P25`
FROM `INFORMATION_SCHEMA`.`COLUMNS` AS pmname
WHERE `TABLE_SCHEMA`='g1109689'
AND `TABLE_NAME`='realtime') AS avg_p25 FROM `realtime` WHERE `City`="Dubai"';
$result2 = mysqli_query($conn, $query2);
$table2['cols'] = array(
array(
'label' => 'PM Type',
'type' => 'string'
),
array(
'label' => 'PM Number',
'type' => 'number'
)
);
while($row2 = mysqli_fetch_array($result2))
{
$sub_array2 = array();
$sub_array2[] = array(
"v" => $row2["avg_p1"]
);
$sub_array2[] = array(
"v" => $row2["avg_p10"]
);
$sub_array[] = array(
"v" => $row2["avg_p25"]
);
$rows2[] = array(
"c" => $sub_array2
);
}
$table2['rows'] = $rows2;
echo $jsonTable2;
?>
我希望餅圖的類別分別是 P1、P10、P25 的平均值。 那么如何創建 SQL 語句到 select 的平均值和列的名稱以及如何將其放入 JSON 表中? 謝謝!
我猜你想要按行平均,即為每個城市添加(p1+p10+p25)/3
而不是按列。 所以你可以試試下面的查詢 -
select city,(tablename.p1 + tablename.p10 + tablename.p25) / 3 as average from tablename
如果要按列計算每個城市的 avg,可以使用 sql 的avg()
方法。
select city, avg(p1),avg(p10),avg(p25) from tablename;
PS:如果你使用 avg() function,你只會得到一個城市的名字
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.