I want to get the 10 most recent rows from a mysql database.
How can I do that?
+----+-------+----+-----------+
| id | value | ap | timestamp |
+----+-------+----+-----------+
And define variables for value, ap, and timestamp... for each row!
like:
$value1 = ?;
$ap1 = ?;
$timestamp1 = ?;
$value2 = ?;
$ap2 = ?;
$timestamp2 = ?;
etc....
The simplest way is probably something like this:
$db = new PDO('mysql:host=<hostname>;port=<port>;dbname=<database name>', '<username>', '<password>');
$query = 'SELECT id, value, ap, `timestamp` '.
'FROM <table> '.
'ORDER BY `timestamp` DESC '.
'LIMIT 10';
$resultset = $db->query($query);
$results = $resultset->fetchAll();
Then you will have a two-dimensional array with 10 sets of the values you want. $results[0]['id'], $results[0]['value'], $results[0]['ap'], and $results[0]['timestamp'], up through $results[9]['id'], etc.
You can get the data like so..
$query = mysql_query("SELECT * FROM `my_table` ORDER BY `timestamp` DESC LIMIT 10");
and you can use the results like so..
while($results = mysql_fetch_object($query)) {
echo $results->value;
echo $results->ap;
echo $results->timestamp;
}
Related
Firstly I am randomly selecting the ID from my table. That part works fine but the next part doesn't. The next part is selecting the ID's row, e.g. if the ID is 6, then it should select all the fields related to 6.
my table is like this:
------------------------------
|ID|Name|Email |Password|
------------------------------
|1 |Amy |H#gmail.com|jaaaaaaa|
------------------------------
|2 |Bob |1#gmail.com|haaukanm|
------------------------------
|3 |Bill|aa#mail.com|fsoji443|
------------------------------
This is my code:
<?php
include('connect.php');
//select a number between min id and max id
$v = "SELECT ID FROM `tblaccounts` ORDER BY RAND() LIMIT 1";
$result = mysqli_query($connection, $v);
$data2 = mysqli_fetch_array($result);
//var_dump($data2);
$c = "SELECT * FROM `tblaccounts` WHERE ID='$data2'";
$cresult = mysqli_query($connection, $c);
$data3 = mysqli_fetch_array($cresult);
var_dump($data3);
?>
The issue is here:
$c = "SELECT * FROM `tblaccounts` WHERE ID='$data2'";
here $data2 is not a single value, its an array and you are trying to compare it in WHERE like a string, that's why the error. Instead try $data2['id'] like:
$c = "SELECT * FROM `tblaccounts` WHERE ID='".$data2['ID']."'";
or
$c = "SELECT * FROM `tblaccounts` WHERE ID=".$data2['ID']; // Sinlge quote is not required if `ID` is `int`
Because your $data2 is an array, this is should work
include('connect.php');
//select a number between min id and max id
$v = "SELECT ID FROM `tblaccounts` ORDER BY RAND() LIMIT 1";
$result = mysqli_query($connection, $v);
$data2 = mysqli_fetch_array($result);
//var_dump($data2);
$c = "SELECT * FROM `tblaccounts` WHERE ID='".$data2['ID']."'";
$cresult = mysqli_query($connection, $c);
$data3 = mysqli_fetch_array($cresult);
var_dump($data3);
You are getting this error as you are comparing array in where clasue.
Your $data is an array like below
$data = array(
'ID'=>2
'Name'=>'Bob',
'Email'=>'1#gmail.com',
'Password'=>'haaukanm'
);// say record with id 2 is fecthed
So use $data['ID'] in your where clause
I was able to apply this line onto phpMyAdmin and it worked just fine.
SELECT id, date_format(`date`, '%m.%d.%Y') as `date` FROM TABLE ORDER BY date DESC LIMIT 1
The problem is that when I added the rest of the code, the recent date shows up blank on the webpage. Am I missing something in this code?
<?php
$query = "SELECT id, date_format(`date`, '%m.%d.%Y') as `date` FROM TABLE ORDER BY date DESC LIMIT 1";
$result = mysql_query($query);
echo "$date";
?>
Any help is appreciated. Thank you.
. Try this
$query = "SELECT id, date_format(`date`, '%m.%d.%Y') as `date` FROM TABLE ORDER BY. date DESC LIMIT 1";
$result = mysql_query($query);
$r = mysql_fetch_assoc($result);
$date = $r['date'];
echo "$date";
You didn't set $date variable. You need to use mysql_fetch_array function for your $result variable.
Ex:
`
$query = "SELECT id, date_format('date', '%m.%d.%Y') as 'date' FROM TABLE ORDER BY date DESC LIMIT 1";
$result = mysql_query($query);
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
print_r($row); }
`
In my table i have date records like 02-04-2016 , 03-01-2016 and 04-01-2016 if i am on 03-01-2016 i want the previous record which is 02-01-2016 But it gives me 01-01-2016 which is the first record of my table. No matter what date i am on.
if(isset($_POST['place'])){
$place = $_POST['place'];
$date = date("Y-m-d", strtotime($_POST['date']));
$classtype = $_POST['classtype'];
$getdate = mysql_query("SELECT * FROM `class` WHERE `city`='$place' AND `clastype`='$classtype' AND `classdate`<'$date' limit 0,1")or die(mysql_error());
$mydt = mysql_fetch_array($getdate);
$mdt = date("d-m-Y", strtotime($mydt[classdate]));
echo $mdt;
}
"SELECT * FROM `class` WHERE `city`='$place' AND `clastype`='$classtype' AND `classdate`<'$date' order by `classdate` desc limit 0,1"
Please use order by clause.
Use ORDER BY clause
Try this:
SELECT *
FROM `class`
WHERE `city`='$place' AND `clastype`='$classtype' AND
`classdate`<'$date'
ORDER BY id DESC
LIMIT 0,1
my database table is named order. it has a row like order. I store values like this 1,2,3,4,5. Now i would like to add to array and from it out info..
I tried to do that but it is not working...
here is my code:
$sql = mysql_query("SELECT * FROM `order` WHERE `id` = ".$_GET['id']." LIMIT 1");
$row = mysql_fetch_assoc($sql);
$sql_order = $row['order'];
$array = array($sql_order);
foreach($array as $x) {
$sql = mysql_query("SELECT * FROM `product` WHERE `id` = ".$x." LIMIT 1");
$row = mysql_fetch_assoc($sql);
$sql_order = $row['order'];
echo $row['product_name'].'<br />';
}
if want check print_r($array) Output
Array ( [0] => 1,23,4,5 )
this one is not working.. i think its supposed to be like this: Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 )
FASTEST APPROACH
You need to use explode() function. Here is an example of it :
<?php
$array = array('0' =>'1,2,3,4,5');
$array = explode(',', $array[0]);
var_dump($array);
?>
Here is your updated code, to get array in that format.
$sql = mysql_query("SELECT * FROM `order` WHERE `id` = ".$_GET['id']." LIMIT 1");
$row = mysql_fetch_assoc($sql);
$sql_order = $row['order'];
$array = array($sql_order);
$array = explode(',', $array[0]);
foreach($array as $x) {
$sql = mysql_query("SELECT * FROM `product` WHERE `id` = ".$x." LIMIT 1");
$row = mysql_fetch_assoc($sql);
$sql_order = $row['order'];
echo $row['product_name'].'<br />';
}
Note this is solution which you are looking for. But it isn't recommended due to reason told to you as comment.
PROPER WAY TO HANDLE THIS
You should ideally normalize your Database so this kind of problem don't come even in future to you.
Here is a proposed table structure change, which you can consider, depending on your need & time.
Remove order column from your table. Add a new table named order_suborders as follows:
| COLUMN | TYPE |
|:-----------|------------:|
|parent_order| int |
| order_id | int |
You can change name of columns and table according to your wish.
Move old data accordingly.
Use query SELECT order_suborders.order_id FROM order, order_suborders WHERE order.id = ".$_GET['id']." AND order.id = order_suborders.parent_order
you can use explod to split with ","
$sql = mysql_query("SELECT * FROM `order` WHERE `id` = ".$_GET['id']." LIMIT 1");
$row = mysql_fetch_assoc($sql);
$sql_order = $row['order'];
//$array = array($sql_order);
$array=explod(",",$sql_order);
foreach($array as $x) {
$sql = mysql_query("SELECT * FROM `product` WHERE `id` = ".$x." LIMIT 1");
$row = mysql_fetch_assoc($sql);
$sql_order = $row['order'];
echo $row['product_name'].'<br />';
}
I'm trying to sort this query by time.
I have a gaming match system. And I want to get a list of next 5 matches from my local time zone.
<?php
include_once "include/dbcompo.php";
$q=mysqli_query($con, "SELECT * FROM kamper ORDER BY tid LIMIT 5");
while($row = mysqli_fetch_array($q))
{
$clan1 = $row['clan1'];
$clan2 = $row['clan2'];
$server = $row['server'];
$tid = $row['tid'];
echo $clan1." ".$clan2." ".$server." ".$tid;
echo "<br />";
}
?>
Add a WHERE clause in your query: WHERE tid > NOW().
With NOW() you take the time of the server, maybe you should replace it with new DateTime(null)->getTimestamp()
Something like that:
<?php
mysqli_query($con, 'SELECT * FROM kamper WHERE tid > NOW() ORDER BY tid LIMIT 5');
// or
mysqli_query($con, 'SELECT * FROM kamper WHERE tid > '.new DateTime(null)->getTimestamp().' ORDER BY tid LIMIT 5');
?>
Two options:
1st option: Make the time field a numeric field and sort in PHP:
$queryResult = mysqli_query($con, $query);
while($row = mysqli_fetch_array($queryResult) {
$oldArray[$row['time'] = $row;
}
$array = ksort($oldArray);
foreach($array as $time=>$row) {
// do something
}
2nd option: Make a subquery
SELECT * FROM (
SELECT * FROM kamper WHERE timezone = 'UTC' ORDER BY tid
) LIMIT 5