i am trying to fetch random records from mysql database , which it worked but i need the records to be also unique when i fetch them as they duplicated on the output, here is my code:
<?
for ($counter = 1; $counter <=5;$counter++)
{
$randomPostSelect = mysql_query("SELECT DISTINCT * FROM beventreservation WHERE (beventStatus='online' OR beventStatus='soldout') ORDER BY RAND() LIMIT 5") or die(mysql_error());
$fetchPosts = mysql_fetch_array($randomPostSelect) or die(mysql_error());
echo '<li>'.$fetchPosts['eventTitle'].'</li>';
echo '</br>';
}
?>
how can i do that ?
You have all the code in a for loop including the code that runs the query; you "extract" 5 rows from db but only fetch the first, and repeat this 5 times. Instead you should run the query once, then loop on your results until you reach the end of the results:
<?
$randomPostSelect = mysql_query("SELECT DISTINCT * FROM beventreservation
WHERE (beventStatus='online' OR beventStatus='soldout') ORDER BY RAND() LIMIT 5")
or die(mysql_error());
while ($fetchPosts = mysql_fetch_array($randomPostSelect))
{
echo '<li><a href="reservation.php?rev='.$fetchPosts['eventId'].'">'.$fetchPosts['eventTitle']
.'</a </li>';
echo '</br>';
}
?>
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);
I want to fetch first five rows and display same five rows at different places on single page, using single query
$cel_bir1=$db->query("SELECT * FROM tbl_birthday WHERE MONTH(Birthday_Date)=$month AND DAY(Birthday_Date)=$day LIMIT 4");
$get_bir=$cel_bir1->fetch(); $count=0;
while($get_bir1=$cel_bir1->fetch())
{
if($count++) echo ',';
echo $get_bir1['Name'];
}
So to get the first 5 rows, you can use Mysql Limit eg: Select * FROM mytable LIMIT 5.
Ok, typically what happens is, When using a PDO,your result-set is stored in an array.
$query = "Select * FROM mytable";
$statement = $db->prepare($query);
$statement->execute();
$productsinfo = $statement->fetchAll();//$productsinfo is the array in question
$statement->closeCursor();
Now to get the values in the array, you can loop through the array using a foreach loop like:
foreach($productsinfo as $productsinfomation):
$productid=$productsinfomation['productid'];
//you can echo $productid or anything you want to do with it here
endforeach;
There is no harm in repeating the foreach loop at different positions on your page.
Le'me know how it works for you.
Have fun coding.
$sql ="SELECT * FROM table_name LIMIT 0,5";
// $conn = your connection to database
$result = $conn->query($sql) or die($conn->error);
$html = '';
while($row = $result->fetch_assoc()){
$html.= $row['colum1'].'<br>'.$row['colum2'];
}
echo $html;
?>
// some more html code
<?php echo $html?>
// some more html code
<?php echo $html?>
// some more html code
<?php echo $html?>
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 trying to dsiplay data from 2 different tables from my mysql database using a while loop.
Currently I can display the data from 1 table and limit the results to 3. I then want to display the first 5 records from another table. If I join the tables I can only display the same number of items from both using LIMIT?
I am using a while loop to display the content from a table called item, using the following code;
$query");
$result2 = #mysql_query($query, $connection)
or die ("Unable to perform query$query");
<?php
while($row= mysql_fetch_array($result))
{
?>
<?php echo $row['item'] ?>
<?php
}
?>
If I start another loop for the data from the next table called movie, however the data is not displayed using the following code;
<?php
while($row= mysql_fetch_array($result2))
{
?>
<?php echo $row['title'] ?>
<?php
}
?>
What is the best way to display the data from the 2 tables?
Many Thanks
I don't know if you forgot to paste a bit of code, but this should work:
<?php
$query = "select * from item order by date, time asc limit 0,3";
$result = mysql_query($query);
while($row= mysql_fetch_array($result))
{
echo $row['item'];
}
$query2 = "select * from movie limit 0,5";
$result2 = mysql_query($query2);
while($row= mysql_fetch_array($result2))
{
echo $row['movie'];
}
?>
You may be able to do it with one SQL Query too:
SELECT i.item, m.movie
FROM (SELECT * FROM item ORDER BY date, time ASC LIMIT 0,3) i,
(SELECT * FROM movie limit 0,5) m
Then in php:
<?php
while($row= mysql_fetch_array($result))
{
echo $row['item'];
echo $row['movie'];
}
?>
But that depends on how you want to format the output.
How do I echo random id numbers from mysql database without repeating numbers?
this is my sample code:
$query = mysql_query("SELECT * FROM store");
$number=mysql_num_rows($query);
for ($count=1; $count<= $number ; $count++)
{
$id = mysql_query ("SELECT id FROM store ORDER BY RAND() LIMIT $number");
$id = mysql_fetch_assoc($id);
$id = $id['id'];
echo $id;
}
It will echo six random numbers but have instances like "1 1 3 2 4 5" where 1 is echoed twice instead of once. thanks in advance
Just order your results by rand and limit their number, your id has to be unique :
SELECT * FROM store ORDER BY RAND() LIMIT 0,6
The Problem is, that you do a SELECT inside of the loop, instead of selecting once and loop over the result.
$query = mysql_query("SELECT * FROM store");
$number=mysql_num_rows($query);
$result = mysql_query ("SELECT id FROM store ORDER BY RAND() LIMIT $number");
while ($row = mysql_fetch_assoc($result)) {
echo $row["id"];
}
BTW: SELECT * to get the number of recordsets is ugly, use SELECT count(id)instead
If you're coming out of php you're probably better off (faster, easier, no locking issues) to randomize your numbers there. And SQL queries inside loops is an antipattern.