Print out certain rows from a table - mysql

Question

The names im using can be changed or removed in the database at times, as it is now i have to change every name in the script when that happends. Can i print it out w/o a IF for example?
<?php
$sql = "SELECT detail,
SUM(IF(depot = 'Huvuddepån', quantity, 0)) AS Huvuddepån,
SUM(IF(depot = 'Uddevalla', quantity, 0)) AS Uddevalla,
SUM(IF(depot = 'Jönköping', quantity, 0)) AS Jönköping,
SUM(IF(depot = 'Polyeten', quantity, 0)) AS Polyeten,
SUM(IF(depot = 'Krackern', quantity, 0)) AS Krackern
FROM quantities
GROUP BY detail";
$result = $conn->query($sql);
echo "<table border='0' cellspacing='3' cellpadding='3'>";
echo "<tr>";
echo "<td width='300'>"."<b>Detalj</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Huvuddepån</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Uddevalla</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Jönköping</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Polyeten</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Krackern</b>"."</td>";
echo "</tr>";
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc())
{
echo "<tr>";
echo "<td>".$row["detail"]."</td>";
echo "<td align='center'>".$row["Huvuddepån"]."</td>";
echo "<td align='center'>".$row["Uddevalla"]."</td>";
echo "<td align='center'>".$row["Jönköping"]."</td>";
echo "<td align='center'>".$row["Polyeten"]."</td>";
echo "<td align='center'>".$row["Krackern"]."</td>";
echo "</tr>";
}
} else {
echo "0 results";
}
echo "</table>";
?>

Answer 1

What about this ? See sqlfiddle
SET #COLUMNS = NULL;
SELECT GROUP_CONCAT(
DISTINCT CONCAT(
'SUM(CASE WHEN depot = "',
depot,
'" THEN quantity ELSE 0 END) AS "',
depot,
'"'
)
) INTO #COLUMNS
FROM quantities;
SET #SQL = CONCAT(
'SELECT
detail,
',#COLUMNS,'
FROM
quantities
GROUP BY
detail'
);
PREPARE stmt FROM #SQL;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
It works with the following table :
CREATE TABLE quantities(
detail INT,
depot VARCHAR(20),
quantity INT
);
INSERT INTO quantities VALUES (1,"Huvuddepån",10);
INSERT INTO quantities VALUES (2,'Uddevalla',15);
INSERT INTO quantities VALUES (2,'Jönköping',20);
INSERT INTO quantities VALUES (3,'Polyeten',10);
INSERT INTO quantities VALUES (1,'Krackern',10);
INSERT INTO quantities VALUES (4,"fo'o6",10);
NOTE : Nevertheless, it will most likely break if one of your depot contains quotes ". If your data might contain such quotes, you should consider using REPLACE to replace those by \" in order to escape them.
The php code you should be using is the following one, I escaped the " in the sql because they weren't and I believe the problem came from here :
<?php
$sql = "SET #COLUMNS = NULL;
SELECT GROUP_CONCAT(
DISTINCT CONCAT(
'SUM(CASE WHEN depot = \"',
depot,
'\" THEN quantity ELSE 0 END) AS \"',
depot,
'\"'
)
) INTO #COLUMNS
FROM quantities;
SET #SQL = CONCAT(
'SELECT
detail,
',#COLUMNS,'
FROM
quantities
GROUP BY
detail'
);
PREPARE stmt FROM #SQL;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;";
$result = $conn->query($sql);
echo "<table border='0' cellspacing='3' cellpadding='3'>";
echo "<tr>";
echo "<td width='300'>"."<b>Detalj</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Huvuddepån</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Uddevalla</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Jönköping</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Polyeten</b>"."</td>";
echo "<td align='center' width='100'>"."<b>Krackern</b>"."</td>";
echo "</tr>";
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc())
{
echo "<tr>";
echo "<td>".$row["detail"]."</td>";
echo "<td align='center'>".$row["Huvuddepån"]."</td>";
echo "<td align='center'>".$row["Uddevalla"]."</td>";
echo "<td align='center'>".$row["Jönköping"]."</td>";
echo "<td align='center'>".$row["Polyeten"]."</td>";
echo "<td align='center'>".$row["Krackern"]."</td>";
echo "</tr>";
}
} else {
echo "0 results";
}
echo "</table>";
?>