Question

I have 2 tables :

tb_a                  tb_2
==================    ===================
|id| data1 |rank |    |id| data2 | rank | 
==================    ===================
|1 | data1 |  1  |    | 1|  dataa|  1   | 
|2 | data2 |  2  |    | 2|  datab|  2   | 
etc..

the data will be sorted depends on the rank. the result must be :

data1
dataa
data2
datab

the code :

$query1= mysql_query("SELECT * FROM tb_a ORDER BY rank ASC");
while ($row1 = mysql_fetch_array($query1)) {
    $data = $row1['data1'];
    echo '<h2 class="title" > '.$data.'  </h2>';
}

$query2= mysql_query("SELECT * FROM tb_b ORDER BY rank ASC");
while ($row2 = mysql_fetch_array($query2)) {
    $data = $row2['data2'];
     echo '<h2 class="title" > '.$data.'  </h2>';
}

the result :

data1
data2
dataa
datab

How to sort them depends on the rank ? thank you 🙂

Answer 1

you can request on the database once by using UNION in your query.

SELECT *
FROM
(
    SELECT id, data1 as `data`, rank
    FROM tb_a
    UNION ALL
    SELECT id, data2 as `data`, rank
    FROM tb_2
) x
ORDER BY x.rank ASC