I'm trying to count the $active_ids from the database. But I'm not figuring out how to do it best. As a disclaimer, I'm still learning MySQL/PHP.
this is what it echo's right now
1, 3, 4, 1, 1
and is what it will look like if it's counted
3, 1 ,1
<?php
$active_ids = '1, 3, 4';
$query = "SELECT * FROM users WHERE id IN ({$active_ids})";
$result = $mysqli->query($query);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo $row['username'], "<br/>";
}
$query = "SELECT COUNT(*) FROM timetable WHERE dj IN ({$active_ids})";
$result = $mysqli->query($query);
while($row = $result->fetch_assoc()){
echo $row['dj'], "<br/>";
}
}
?>
I don't really know PHP, but I know SQL. It sounds like you want to use a GROUP BY clause, like this:
select dj, count(*) as n from timetable
where dj in ({$active_ids})
group by dj
Each row selected will have two columns. The first column (named “dj”) is the dj's user id, and the second column (named “n”) is the number of entries in timetable with that dj's id. You should be able to print the count like this:
echo $row['n'], "<br/>";
Related
can someone help me on the proper way of using a variable with multiple values in MySQL LIKE clause?
by the way, I have two tables teacher and student.
Teacher table contains. (fname,lname,subject,yr,sec) columns and for the student table (lrn,yr,sec)
what I'm trying to achieve is to count the total number of students of the teacher from all sections.
Here's my query for getting teacher's sections:
<?php
$result= mysqli_query($con, "select *from teacher where lname
= 'Uy' and subject = 'Science & Technology 7'" );
while($rowx = mysqli_fetch_array($result)) {
$section = $rowx['sec'];
}
?>
echoing $section output this: Our Lady of FatimaOur Lady of Guadalupe
Heres my query to count the students.
<?php
$ratequery = mysqli_query($con, "SELECT *,
(SELECT COUNT(*) FROM student WHERE
sec LIKE '%$section%') AS responseCount FROM student");
$rateresult = mysqli_fetch_array($ratequery);
?>
Output: the count works but only the first value [Our Lady of Fatima] of $section is getting recognized by LIKE clause, so only 1 section is getting counted.
by the way, sorry for my bad English and explanation.
Use Section as a input for second query:
<?php
$final_result = array();
$result= mysqli_query($con, "select *from teacher where lname
= 'Uy' and subject = 'Science & Technology 7'" );
while($rowx = mysqli_fetch_array($result))
{
$section = $rowx['sec'];
$ratequery = mysqli_query($con, "SELECT *, (SELECT COUNT(*) FROM student WHERE
sec =$section) AS responseCount FROM student");
$rateresult = mysqli_fetch_array($ratequery);
array_push($final_result,array("section"=>$section,"rateresult"=>$rateresult));
}
var_dump($final_result); // Display section wise data
?>
somehow I have managed to achieve my goal it but in other way . I used WHERE IN clause instead of LIKE clause. stored my query results into an array.. then used implode to add seperator.
Thanks for the help mr. #ashnu
<?php
$query="$con, select *from teacher where lname = 'Uy' and subject = 'Science & Technology 7'";
$result = mysqli_query($query) or die;
$sections = array();
while($row = mysqli_fetch_assoc($result))
{
$sections[] = $row['sec'];
}
$string = implode("','",$sections)
?>
<?php
$ratequery = mysqli_query($con, "SELECT *,
(SELECT COUNT(*) FROM student WHERE sec IN ('$string')) AS responseCount FROM student");
$rateresult = mysqli_fetch_array($ratequery);
?>
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);
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 am using the following MySQL query to generate a table for users in a database. The query is designed to just return one row for each user, even though there are multiple rows for each user. This works fine, however I also need to calculate the number of unique entries for each user, to enter into the table where it states HERE. Do I need to use another query to return the count for all entries, and if so how do I integrate this with the code I already have?
$query="SELECT from_user, COUNT(*) AS num FROM tracks GROUP BY from_user ORDER BY COUNT(*) DESC";
$result=mysql_query($query) or die(mysql_error());
while ($row = mysql_fetch_array($result)) {
$user = $row['from_user'];
echo "<tr>";
echo "<td>".$user."</td>";
echo "<td>uploads (**HERE**)</td>";
echo "<td>favourites (count)</td>";
echo "</tr>";
}
?>
</table>
Because you've already created the custom field 'num', you can use that to get the count!
Add the following line after user = ...
$count = $row['num'];
Then you can
echo "<td>uploads ($count)</td>";
It miss your table stucture to know your field name, but, if i well understand your question you can use count + distinct in mysql.
You can check this answer too.
SELECT DISTINCT(from_user) AS user,
COUNT(from_user) AS num
FROM tracks
GROUP BY from_user
ORDER BY num DESC";
For the second problem you can doing a second query, or do a join tracks .
I think, in your case it's easier to you to do se second query inside the loop to get all detail from 'user' result.
$query1="SELECT DISTINCT(from_user), COUNT(*) AS num
FROM tracks
GROUP BY from_user
ORDER BY COUNT(*) DESC";
$query2="SELECT * FROM tracks";
$result1=mysql_query($query1) or die(mysql_error());
$result2=mysql_query($query2) or die(mysql_error());
$user_array = array();
while ($row = mysql_fetch_array($result1)) {
$user = $row['from_user'];
$num = $row['num'];
$uploads_array = array();
while ($sub_row = mysql_fetch_array($result2)) {
if( $sub_row['from_user'] == $user ) {
//for example only due to the unknown structure of your table
$uploads_array[] = array(
"file_name" => $sub_row['file_name'],
"file_url" => $sub_row['file_url']
);
}
}
$user_array[] = array(
"name" => $user,
"num_entry" => $num,
"actions" => $uploads_array
);
}
// now the table with all data is stuctured and you can parse it
foreach($user_array as $result) {
$upload_html_link_arr = array();
$user = $result['name'];
$num_entry = $result['num_entry'];
$all_actions_from_user_array = $result['actions'];
foreach($all_actions_from_user_array as $upload) {
$upload_html_link_arr[] = sprintf('%s', $upload["file_url"],$upload["file_name"]);
}
$upload_html_link = implode(', ',$upload_html_link_arr);
$full_row = sprintf("<tr><td>%s</td><td>uploads : %s</td><td>favourites (%d)</td></tr>", $user, $upload_html_link, $num_entry);
// now just echo the full row or store it to a table for the final echo.
echo $full_row;
}
I hope this help, mike
I have a MySQL database containing a user's country and whether they are an individual or an organisation. The field names are 'country' and 'type'.
Using PHP, I'd like to 'count' the number of countries, the number of individuals and the number of organisations in the database and then display the numbers in the following example format:
<p>So far, <strong>500</strong> individuals and <strong>210</strong> organisations from <strong>40</strong> countries have registered their support.</p>
I am currently listing the total number of records using the below code if this helps:
<?php
$link = mysql_connect("localhost", "username", "password");
mysql_select_db("database_name", $link);
$result = mysql_query("SELECT * FROM table_name", $link);
$num_rows = mysql_num_rows($result);
echo " $num_rows\n ";
?>
My PHP / MySQL skills are very limited so I'm really struggling with this one.
Many thanks in advance!
Ben
To get the number of countries:
SELECT COUNT(DISTINCT country) AS NumCountries FROM tableName
To get the number of individuals, or the number of organisations:
SELECT COUNT(*) AS NumIndividuals FROM tableName WHERE type = 'individual'
SELECT COUNT(*) AS NumOrganisations FROM tableName WHERE type = 'organisation'
What you are looking for is a count based on a grouping. Try something like this:
$sql = "SELECT type, count(*) as cnt FROM users GROUP BY type";
$result = mysql_query($sql);
$counts = array();
while ($row = mysql_fetch_assoc($result)) {
$counts[$row['type']] = $row['cnt'];
}
This will give you an array like
Array (
'individual' => 500,
'organization' => 210
)
For counting the countries, use the first statement as posted by Hammerite.
EDIT: added a verbose example for counting the countries
$sql = "SELECT COUNT(DISTINCT country) AS NumCountries FROM users";
$result = mysql_query($sql);
$number_of_countries = 0;
if ($row = mysql_fetch_assoc($result)) {
$number_of_countries = $row['NumCountries'];
}
This altogether you can then print out:
printf('<p>So far, <strong>%d</strong> individuals and <strong>%d</strong> '.
'organisations from <strong>%d</strong> countries have registered '.
'their support.</p>', $counts['individual'], $counts['organization'],
$number_of_countries);
The answer is to retrieve the answer by using the COUNT(*) function in SQL:
SELECT COUNT(*) AS individual_count FROM user WHERE type = 'individual';
SELECT COUNT(*) AS organization_count FROM user WHERE type = 'organization';
SELECT COUNT(*) AS country_count FROM user GROUP BY country;
The last will group your query set by the country name, and will result in one row for each country. Using COUNT on this result set will give the count of distinct coutries.
You can then fetch this value by using mysql_fetch_assoc on your $result from mysql_query, and the answer will be contained in 'invididual_count', 'organization_count' and 'country_count' for each query.
Thank you for all of your help with this (especially Cassy).
I think it's worthwhile displaying the full code in case anybody else comes across a similar requirement in the future:
<?php
$link = mysql_connect("localhost", "username", "password");
mysql_select_db("database_name", $link);
$sql = "SELECT type, COUNT(*) as cnt FROM table_name GROUP BY type";
$result = mysql_query($sql);
$counts = array();
while ($row = mysql_fetch_assoc($result)) {
$counts[$row['type']] = $row['cnt'];
}
$sql = "SELECT COUNT(DISTINCT country) AS NumCountries FROM table_name";
$result = mysql_query($sql);
$number_of_countries = 0;
if ($row = mysql_fetch_assoc($result)) {
$number_of_countries = $row['NumCountries'];
}
printf('<p><strong>So far, <em class="count">%d</em> individuals and <em class="count">%d</em> organisations from <em class="count">%d</em> countries have registered their support.', $counts['Individual'], $counts['Organisation'], $number_of_countries); ?>
If you're just looking for the number of rows returned try this:
$result = mysql_db_query($db, $query);
$num_rows = mysql_num_rows($result);
Another option would be to execute a separate query with the mysql count function and use the result from that.