I'm developing a website using HTML, PHP and MySQL to access a database. On one page I present a table with data from that database. This is some of the code I'm using:
$sql1 = "SELECT * FROM MyTable ORDER BY ID ASC";
$rs1 = mysqli_query($link,$sql1);
(...)
while($row1 = mysqli_fetch_assoc($rs1)) {
echo "<tr><td>".$row1['ID']."</td><td>".$row1['Field1']."</td><td></td><td>".$row1['Field2']."</td><td>".$row1['Field3']."</td></tr>\n" ;
}
Notice the empty <td></td>
? That's because I want to have there the number of time a given ID appears on two other tables (there are foreign keys involved, obviously). I have sorted out the code I need for that:
$sql2 = "SELECT (SELECT COUNT(*) FROM MyTable2 WHERE ID2=$row1['ID'])+(SELECT COUNT(*) FROM MyTable3 WHERE ID2=$row1['ID']) AS total";
However, I'm struggling with figuring out a way to add this result to the other table. Any help?
try with this.. it inserts the total to an table after selecting the count.
"INSERT INTO total_table (total)
SELECT (SELECT COUNT(*) FROM MyTable2 WHERE ID2=$row1['ID'])+(SELECT COUNT(*) FROM MyTable3 WHERE ID2=$row1['ID']) AS total
WHERE cid = 2"
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