Hello so I have this table with some equal values
And this is my query so far
$stmt = $dbc->query("SELECT weight, GROUP_CONCAT(id) AS ids FROM tbl_weight GROUP BY weight HAVING COUNT(*) > 1");
while($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
echo $row['ids'] . "<br />";
}
And the output when I run this query is
What I actually want to get is like this
How is this possible?
Related
I'm trying to get the latest info about some specific person, and I'm using a query like
SELECT * FROM Table WHERE Name LIKE 'Peter' ORDER BY ID DESC LIMIT 1
and
SELECT * FROM Table WHERE Name LIKE 'Mary' ORDER BY ID DESC LIMIT 1
because in the Table each day will insert new data for different person at the instant of updating it (for record reference), so I would like to print out a few persons latest info by "ORDER BY ID DESC LIMIT 1"
I have tried to print it out with "mysqli_multi_query" and "mysqli_fetch_row"
like
$con=mysqli_connect($localhost,$username,$password,'Table');
$sql = "SELECT * FROM Table WHERE Name LIKE 'Peter' ORDER BY ID
DESC LIMIT 1 ";
$sql .= "SELECT * FROM Table WHERE Name LIKE 'Mary' ORDER BY ID
DESC LIMIT 1";
// Execute multi query
if (mysqli_multi_query($con,$sql))
{
do
{
// Store first result set
if ($result=mysqli_store_result($con)) {
// Fetch one and one row
while ($row=mysqli_fetch_row($result))
{
echo '<tr>'; // printing table row
echo '<td>'.$row[0].'</td>';
echo '<td>'.$row[1].'</td>';
echo '<td>'.$row[2].'</td>';
echo '<td>'.$row[3].'</td>';
echo '<td>'.$row[4].'</td>';
echo '<td>'.$row[5].'</td>';
echo '<td>'.$row[6].'</td>';
echo '<td>'.$row[7].'</td>';
echo '<td>'.$row[8].'</td>';
echo '<td>'.$row[9].'</td>';
echo '<td>'.$row[10].'</td>';
echo '<td>'.$row[11].'</td>';
echo '<td>'.$row[12].'</td>';
echo '<td>'.$row[13].'</td>';
echo '<td>'.$row[14].'</td>';
echo'</tr>'; // closing table row
}
// Free result set
mysqli_free_result($result);
}
}
while (mysqli_next_result($con));
}
mysqli_close($con);
?>
In the result page , it doesn't show any error message , but no results are printed.
The individual queries were tested.
Please advise, much thanks
Is there another way to keep the query simple, so there is no need to use mysqli_multi_query?
Best practice indicates that you should always endeavor to make the fewest number of calls to the database for any task.
For this reason, a JOIN query is appropriate.
SELECT A.* FROM test A INNER JOIN (SELECT name, MAX(id) AS id FROM test GROUP BY name) B ON A.name=B.name AND A.id=B.id WHERE A.name IN ('Peter','Mary')
This will return the desired rows in one query in a single resultset which can then be iterated and displayed.
Here is an sqlfiddle demo: http://sqlfiddle.com/#!9/2ff063/3
P.s. Don't use LIKE when you are searching for non-variable values. I mean, only use it when _ or % are logically required.
This should work for you:
$con = mysqli_connect($localhost,$username,$password,'Table');
// Make a simple function
function personInfo($con, $sql)
{
$result = mysqli_query($con, $sql);
if(mysqli_num_rows($result) > 0)
{
while($row = mysqli_fetch_array($result))
{
echo '<table>
<tr>';
for($i=0; $i < count($row); $i++) echo '<td>'.$row[$i].'</td>';
echo '</tr>
</table>';
}
}
}
$sql1 = "SELECT * FROM Table WHERE Name='Peter' ORDER BY ID DESC LIMIT 1 ";
$sql2 = "SELECT * FROM Table WHERE Name='Mary' ORDER BY ID DESC LIMIT 1";
// Simply call the function
personInfo($con, $sql1);
personInfo($con, $sql2);
$sql = "SELECT title, article, filename, caption FROM articles
INNER JOIN images WHERE articles.image_id = images.image_id";
$result = $conn->query($sql);
$row = $result->fetch_assoc();
var_dump($row);
This only grabs the first row in the db when what I need is for it to grab all rows. How can I achieve this?
fetch_assoc() returns the next row of the result set with each call, so you need to call it in a loop like this:
while($row = $result->fetch_assoc()) {
var_dump($row);
}
The loop ends when $row = null (i.e. there's no more rows in the result set).
Please have a look at the Quick start guide, more specifically the Executing statements chapter. Right from that page:
$mysqli->real_query("SELECT id FROM test ORDER BY id ASC");
$res = $mysqli->use_result();
echo "Result set order...\n";
while ($row = $res->fetch_assoc()) {
echo " id = " . $row['id'] . "\n";
}
How to display only one row at random at the same time from DB. Everything works fine, but all rows are displayed. thanks
<?php
$sql = "SELECT id,name FROM table ";
$rows = array();
$result = $objCon->query($sql);
while($row = $result->fetch_assoc())
{
$rows[] = $row;
}
shuffle($rows);
echo '<ol>';
foreach($rows as $row)
{
echo '<li><h3>'.$row['id'].' = '.$row['name'].'</h3></li>';
}
echo '</ol>';
?>
Change your SQL request:
SELECT id,name FROM table ORDER BY RAND() LIMIT 1;
You can do it using PHP:
....
shuffle($rows);
$randomRow = reset($rows);
....
But the better way is to change your SQL query:
$query = "SELECT id, name FROM table ORDER BY RAND() LIMIT 1;"
<?php
$sql = "
SELECT id, name
FROM table
ORDER BY RAND()
LIMIT 1 ";
$result = mysql_query($sql);
// As you are only return a single row you do you require the while()
$row = mysql_fetch_array($result);
echo '<ol>';
echo '<li><h3>'.$row['id'].' = '.$row['name'].'</h3></li>';
echo '</ol>';
?>
By adding an ORDER BY RAND() in your sql query you are asking MySQL to randomly order the results then at a LIMIT to restrict the number of rows you would like returned.
The example code is written based on selecting a single row. If you would like more, e.g. 5, you will need to add a while loop.
I have database with 8 different product category for download.
pic, app, ebo, tem, des, cod, mus, cat
I'd like to count clients total downloaded products and total downloads of each product category.
Maximum daily limit downloads for category product is 3.
When user log in should see how many downloads remain.
Here is working code
$query = "SELECT COUNT(*) as sum FROM service_downloads where client_id like '$client'";
$result = mysql_query($query) or die(mysql_error());
// Print out result
while($row = mysql_fetch_array($result))
{
echo "You have downloaded". $row['sum'] ." products.";
echo "<br />";
}
$query = "SELECT COUNT(*) as sum FROM service_downloads where client_id like '$client' and product like 'pic'";
$result = mysql_query($query) or die(mysql_error());
// Print out result
while($row = mysql_fetch_array($result))
{
echo "". $row['sum'] ." downloaded pictures";
$leftovers = 3 - $row['sum'];
echo " $leftovers pictures remain for download";
echo "<br />";
}
$query = "SELECT COUNT(*) as sum FROM service_downloads where client_id like '$client' and product like 'app'";
$result = mysql_query($query) or die(mysql_error());
// Print out result
while($row = mysql_fetch_array($result))
{
echo "". $row['sum'] ."downloaded applications";
$leftovers = 3 - $row['sum'];
echo " $leftovers applications remain for download.";
echo "<br />";
}
$query = "SELECT CO.... This procedure repeat eight times for different product category.
result
You have downloaded 12 products.
3 downloaded pictures 0 pictures remain for download.
1 downloaded applications 2 applications remain for download.
3 downl.......
You could use a GROUP BY statement to group your results.
SELECT COUNT(`Product`) AS `Sum`, `Product`
FROM `service_downloads`
WHERE `client_id` = '<client_id>'
GROUP BY `Product`
Then you can use one while statement to loop through each product:
// Print out result
while($row = mysql_fetch_array($result))
{
echo "". $row['Sum'] ."downloaded " . $row['Product'];
$leftovers = 3 - $row['Sum'];
echo " $leftovers " . $row['Product'] . " remain for download.";
echo "<br />";
}
$query = "SELECT COUNT(*) as sum,product FROM service_downloads where client_id like '$client' GROUP BY product";
$result = mysql_query($query) or die(mysql_error());
// Print out result
while($row = mysql_fetch_array($result))
{
echo "You have downloaded". $row['sum'] ." ".$row['product'];
echo "<br />";
}
This should work
You should breakdown the quantity of downloads per category in one query:
SELECT product,COUNT(*)
FROM service_downloads
WHERE client_id like '$client';
I also don't think you need to use LIKE; you probably want to use =
You can get a single result set with all the sums in it with this query.
SELECT COUNT(*) as sum, product
FROM service_downloads
WHERE client_id = '$client'
AND PRODUCT IN ('pic', 'app', 'abc', 'def', 'ghi')
GROUP BY product WITH ROLLUP
ORDER BY product NULLS FIRST
This will give you one row for each specific product and a summary (rollup) row with a NULL value in the product column.
If this query takes a long time create an index on (client, product) and it should go pretty fast.
If you are showing this data frequently, which is what it sounds like, then you should have a separate table that represents those SUMs and is index by CLIENT_ID.
You can then increment/decrement that value each time you add a new entry.
For example, when you add a new row to service_downloads with an entry in 'pic' for CLIENT_ID 1, then you would also increment this shortcut table:
UPDATE service_counts SET pic=pic+1 WHERE client_id=1;
I have the following code to pull a random value from a database.
$result = mysqli_query($con,"SELECT column1 FROM table1
ORDER BY RAND()
LIMIT 1");
while($row = mysqli_fetch_array($result))
{
echo $row['column1'];
echo "<br>";
}
At the moment I only have about 10 values in total. Sometimes they appear more than once in a row upon refresh.
Can the query be amended to show a random value that is not the current value?
in order to do that you need to somehow remember the last row.
Then do something like this
$result = mysqli_query($con,"SELECT column1 FROM table1
where id_of_your_row != ".mysqli_real_escape_string($id_of_your_last_row)."
ORDER BY RAND()
LIMIT 1");
For remembering the last row, you could use sessions.
Your whole code could look like this.
// sessions need to bestarted
$result = mysqli_query($con,"SELECT column1 FROM table1
where column1 != ".(isset($_SESSION["lastid"]) ? mysqli_real_escape_string($_SESSION["lastid"]) : '')." ORDER BY RAND()
LIMIT 1");
while($row = mysqli_fetch_array($result))
{
echo $row['column1'];
$_SESSION["lastid"] = $row['column1'];
echo "<br>";
}