php mysql using nested query - php

I am trying to find if two runners have ever ran in the same race. The two runners are Peter Smith and Diane Peters.
$resultRaceType = mysqli_query($db,"SELECT DISTINCT date,time FROM results where runner = 'Peter, Smith' ");
while($row = mysqli_fetch_array( $resultRaceType ))
{
$resultRaceType1 = mysqli_query($db,"SELECT * FROM results where date = ' " . $row['date'] . " ' and time = ' " . $row['time'] . " ' and runner = 'Diane, Peters'");
while($row1 = mysqli_fetch_array( $resultRaceType1 ))
{
echo "<tr >";
echo "<td>";
echo $row1['date'];
echo " - " . $row1['time'];
echo "</td>";
echo "<tr>";
}
}
The above code works, but only if I limit the first select to LIMIT 50. So I can see that it is timing out. My table has over 100K rows. I know I am doing something wrong but cant see what it is.
Thanks for any help you guy's can give me.

Try:
SELECT a.date, a.time FROM results a
JOIN results b ON (a.date = b.date AND a.time = b.time)
WHERE a.runner='Peter, Smith' AND b.runner='Diane, Peters';

Related

Mysql Query Getting Item as ID in 2 different tables

Im sorry for my bad english but this is the best i can.
I am trying to make a script that get's the item values of one line in my
for this example i'll be using the row with ID 2.
The first query is working correctly and getting the 2 values of 1items and 2items and deletes the ; that comes with it.
But the second part seems a little bit harder and i can't solve it.
The query is getting id, base_item from the table
The last 2 Outputs marked red are the one's that are matching 1items & 2items
I'm trying to let the if statement filter the $item1 as id in the item table and output the baseitem of the found row
same goes for item2
I'm using MySQL & MySQLi because this cms doesnt support newer versions of PHP yet.
<?php
$query = "SELECT * FROM logs_client_trade ORDER by id DESC";
$result = mysql_query($query) or die(mysql_error());
while($row = mysql_fetch_array($result)){
$item1 = rtrim($row['1items'],"; ");
$item2 = rtrim($row['2items'],"; ");
echo("<tr>");
echo("<td>" . $row['id'] . "</td>");
echo("<td>" . $row['1id'] . "</td>");
echo("<td>" . $row['2id'] . "</td>");
$userinfo = "SELECT id, base_item FROM items LIMIT 1";
$result2 = mysql_query($userinfo) or die(mysql_error());
while($row2 = mysql_fetch_assoc($result2)){
echo("<td>");
if($row2['id'] == $item1){ echo $row2['baseitem']; } else echo "Not available";
echo ("</td>");
echo("<td>");
if($row2['id'] == $item1){ echo $row2['baseitem']; } else echo "Not available";
echo ("</td>");
}
$tradetime = $row['timestamp'];
$date = date("d M Y - H:i:s", $tradetime);
echo("<td>$date</td></tr>");
}
?>
You forgot the while loop for the second query:
$userinfo = mysql_query("SELECT id, base_item FROM items");
while($get2 = $userinfo->fetch_assoc()) {
$baseid = $get2['id'];
$baseitem = $get2['baseitem'];
echo("<tr>");
[...]
}
In addition to that, your code is a mess. In the second loop you are still listing the rows from the logs table... I suggest you to review carefully your code, being careful on how you are using the different $row and $get2 arrays.
You can use a JOIN to get all of the info with one SQL statement:
SELECT *
FROM `logs_client_trade` a
LEFT JOIN `items` b
ON REPLACE(a.`1items`,';','') = b.`id`
LEFT JOIN `items` c
ON REPLACE(a.`2items`,';','') = c.`id`
ORDER by a.`id` DESC
UPDATE:
Here's the PHP code that will run the query and output the table rows. I've specified the column names based on the code in the original question.
<?php
$query = "SELECT
a.`id`,
a.`1id`,
a.`2id`,
a.`1items`,
a.`1items`,
IFNULL(b.`baseitem`,'Not Available') as `baseitem1`,
IFNULL(c.`baseitem`,'Not Available') as `baseitem2`,
DATE_FORMAT(a.`timestamp`,'%d %m %Y - %H:%i:%s') as `tradetime`
FROM `logs_client_trade` a
LEFT JOIN `items` b
ON REPLACE(a.`1items`,';','') = b.`id`
LEFT JOIN `items` c
ON REPLACE(a.`2items`,';','') = c.`id`
ORDER by a.`id` DESC
";
$result = mysql_query($query) or die(mysql_error());
while($row = mysql_fetch_array($result)){
$item1 = rtrim($row['1items'],"; ");
$item2 = rtrim($row['2items'],"; ");
echo "<tr>\r\n";
echo " <td>" . $row['id'] . "</td>\r\n";
echo " <td>" . $row['1id'] . "</td>\r\n";
echo " <td>" . $row['2id'] . "</td>\r\n";
echo " <td>" . $row['baseitem1'] . "</td>\r\n";
echo " <td>" . $row['baseitem2'] . "</td>\r\n";
echo " <td>" . $row['tradetime'] . "</td>\r\n";
echo("</tr>\r\n");
}
?>

need help where to put my datediff query in this code

Were can i insert my datediff query in this code
$search = $_POST['search'];
$result = mysql_query("SELECT * FROM documents where docnum "My Search Bar"='$_SESSION[test2]' and doctitle LIKE '%$search%' order by docprim desc");
while($row = mysql_fetch_array($result))
{
echo "<tr class ='hovered'>";
echo "<td width = '100px' class='text-left'>";
echo $row['docnum'];
echo "</td>";
echo "<td width = '100px' class='text-left'>";
echo $row['datein']." to ".$row['dateout'];
echo "</td>";
}
this is a sample of my code. i want to add duration from datein and dateout field from my table.
You need to modify your SQL Query String.
$startdate = date('Y-m-d');
$enddate = date('Y-m-d', strtotime("-3 days"));
$result = mysql_query("SELECT * FROM documents where docnum ='".$_SESSION['test2']."' and doctitle LIKE '%$search%' and DATEDIFF('".$startdate."', '".$enddate."') > 0 order by docprim desc");
Also your SQL Query string has issues. Let me know if you need help with that as well.
Hope this helps.
Insert TIMESTAMPDIFF before '*' in sql-query:
SELECT TIMESTAMPDIFF(SECOND, d.datein, d.dateout) AS timediff, m.* FROM documents m;
and use as:
echo $row['datein']." to ".$row['dateout'] . " (" . $row['timediff'] . ")" ;
$row['timediff'] will show seconds.

Fastest way for selecting something like this

I want to select faster than this my page load is very slow when executing the script.
$bmw= mysqli_query($con,"SELECT * FROM cars WHERE name='bwm'
ORDER BY date DESC LIMIT 1"); $mercedes= mysqli_query($con,"SELECT * FROM cars
WHERE name='mercedes' ORDER BY date DESC LIMIT 1");
$audi= mysqli_query($con,"SELECT * FROM cars WHERE name='audi'
ORDER BY date DESC LIMIT 1");
$skoda= mysqli_query($con,"SELECT * FROM cars WHERE name='skoda'
ORDER BY date DESC LIMIT 1");
And echo it out like here below, like that the page load is very slow.
while($row = mysqli_fetch_array($bmw)) { echo $row['name'] . " " .
$row['date'];
}
while($row = mysqli_fetch_array($mercedes)) { echo $row['name'] . " "
. $row['date'];
}
while($row = mysqli_fetch_array($audi)) { echo $row['name'] . " " .
$row['date'];
}
Thanks in advance
There is nothing wrong in the queries you wrote, your performance issue may be due to :
missing indexes on name and date : create indexes on name and date
cars database too big for your hardware : new hardware/partitionning/redesign
network link slow : solution provided by Lacy K is interesting as there is only one query sent to mysql
You could also improves performance a bit by selecting only name and date instead of *
select name, date from ...
Why not selecting all make at once like this:
$q= mysqli_query($con,"SELECT * FROM cars WHERE name IN ('bwm', 'mercedes', 'audi', 'skoda') ORDER BY date DESC LIMIT 1");
while($row = mysqli_fetch_array($q)) {
if($row['name'] == 'bmw'){
echo $row['name'] . " " . $row['date'];
}
elsif($row['name'] == 'mercedes'){
echo $row['name'] . " " . $row['date'];
}
elsif($row['name'] == 'audi'){
echo $row['name'] . " " . $row['date'];
}
elsif($row['name'] == 'skoda'){
echo $row['name'] . " " . $row['date'];
}
else{
echo $row['name'] . " " . $row['date'];
}
}

Output distinct values in SQL column with PHP

I have a table with two collumns (shortened), NAME and CATEGORY.
I want to output the number of distinct categorys. For an examle: Sport : 5 , Houses : 10.
I use this one:
$test = mysqli_query($con,"SELECT category, COUNT(category) as count FROM tablename GROUP BY category ORDER BY count DESC");
This work then I run the code in SQL Shell, but I have no clue on how to output it in PHP. I have searced Google up and down without any successfull solution.
Any help?
I want to output it in a table format.
EDIT: Here is my full code: (tablename is changed, and $con is removed)
$test = mysqli_query($con,"SELECT DISTINCT lkategori, COUNT(lkategori) as count FROM tablename GROUP BY lkategori ORDER BY count DESC");
while($row = mysql_fetch_array($test)) {
echo $row['lkategori'] . ":" . $row['count'];
die("test");
}
$test = mysqli_query($con,"SELECT DISTINCT lkategori, COUNT(lkategori) as count FROM tablename GROUP BY lkategori ORDER BY count DESC");
echo "<table border='1'>";
while($row = mysqli_fetch_array($test)) {
echo "<tr>";
echo "<td>" . $row['lkategori'] . "</td>";
echo "<td>" . $row['count'] . "</td>";
echo "</tr>";
}
echo "</table>";
This will output all the categories and the count returned by the sql statement into a table. Also as a sidenote you should look into PDO.
EDIT: to make sure you do get the distinct values you should use the DISTINCT keyword in your sql statement:
$test = mysqli_query($con,"SELECT DISTINCT category, COUNT(category) as count FROM tablename GROUP BY category ORDER BY count DESC");
use this
while($row = mysqli_fetch_array($test)) {
echo $row['lkategori'] . ":" . $row['count'];
die("test");
}
Thanks

Php in MYSQL aggrate function not working

$result = mysql_query("SELECT avg(r.rate) FROM rate r where ImgName='1'");
this php is not working.
Originally my code is
<?php
$con = mysql_connect("localhost","root","sql");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("photogallery", $con);
$result = mysql_query("SELECT avg(r.rate) FROM rate r ");
echo "<table border='0' cellspacing='5'>";
echo "<th> Average Rating </td>";
while($row = mysql_fetch_array($result))
{
echo "<tr>";
echo "<td> " . $row['rate'] . "</td>";
echo "</tr>";
}
echo "</table>";
mysql_close($con);
?>
the above is not showing any out put.
but modify code i.e. then its workin.
$result = mysql_query("SELECT r.rate FROM rate r ");
but i want to aggregate function
thanks in advance
you can use an alias:
SELECT avg(r.rate) AS rate_average
FROM rate r
WHERE ImgName='1'
and then output:
echo "<td> " . $row['rate_average'] . "</td>";
Your query is producing a scalar rather than a set of rows. If you want to get the average rate per item then you should do something like:
SELECT avg(r.rate) FROM rate r GROUP BY ItemIdColumn
And yes, if you want to fetch the value by column name, you should use an alias, like knittl mentioned.

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