PHP MYSQL $row[$variable] - php

I am trying to work around with dynamic table creation and data fetching. I am trying to get the data using following code :
$myQuery = "SELECT ".$col_name." FROM ".$tabname." WHERE sampleid='".$sid."'";
$result = mysql_query($myQuery);
$row = mysql_fetch_array($result);
echo "<br>".$row['$col_name'];
But, I am unable to get any data back. I checked printing the query and running it in php my admin and its working as I want. But I guess variable in array might not be working I guess.
Please help me regarding the same. Thanks.
The Whole loop looks something like this :
$myQuery = "SELECT * FROM information_schema.columns WHERE table_name = '$tabname'";
$re = mysql_query($myQuery);
while($row = mysql_fetch_array ($re)){
if(!empty ($row)){
$col_name = $row['COLUMN_NAME'];
$myQuery = "SELECT ".$col_name." FROM ".$tabname." WHERE sampleid='".$sid."'";
echo "<br>".$myQuery;
$reqq = mysql_query($myQuery);
$roww = mysql_fetch_array($reqq);
echo "<br>".$roww[$col_name];
}
}

You are fetching an array, not an assoc array. Use this:
echo "<br>".$row[0];
Edit: Having looked a little more, this may not be correct. You can set fetch_array to return assoc arrays.
You cannot parse variables through single quotes '
echo $row['col_name']; // manually typed string.
or
echo $row[$col_name];
or
echo $row["$col_name"];

You tried that->
echo "<br>".$row[$col_name];
OR
$myQuery = "SELECT ".$col_name." FROM ".$tabname." WHERE sampleid='".$sid."'";
$result = mysql_query($myQuery);
$row = mysql_fetch_assoc($result);
echo "<br>".$row[$col_name];
Cause like said #Fluffeh it's not a associative array

Have you tried looping through the results array as such:
while($row = mysql_fetch_array($result)) {
echo $row['col_name'];
echo "<br />";
}

I would suggest the following solution. Give the parameter $col_name and AS Col_Name
Then the $row['Col_Name'] can always be set to the parameter no matter what the value.
$myQuery = "SELECT ".$col_name." AS Col_Name FROM ".$tabname." WHERE sampleid='".$sid."'";
$result = mysql_query($myQuery);
$row = mysql_fetch_array($result);
echo "<br>".$row['Col_Name'];

Related

Select query for getting a single value is not working

$sql = "SELECT temail FROM teacherusers WHERE tfullname='$teachername' limit 1";
$result = mysql_query($sql);
$value = mysql_fetch_object($result);
$teacheremail2 = $value->temail;
echo $teacheremail2;
echo $teacheremail2 returns nothing.
$teachername is valid and i have checked multiple times.
It should be a two-dimensional array , you need
$value[0]->temail
The result of mysql_fetch_object($result) is an object(stdClass).
The explanation of object(stdClass) ican be found at this link
$sql = "SELECT temail FROM teacherusers WHERE tfullname='$teachername' limit 1";
$result = mysql_query($sql);
while ($value = mysql_fetch_object($result))
{
$teacheremail2 = $value->temail;
echo $teacheremail2;
}
First off, you'll want to run the query directly against your database to ensure that the query returns some kind of result.
Secondly, if that works, you'll want to echo $value directly to check that you are getting results back on the webpage.
Then you can check if temail is a field of $value
$sql = "SELECT temail FROM teacherusers WHERE tfullname='$teachername' limit 1";
$result = mysql_query($sql);
while ($value = mysql_fetch_object($result))
{
$teacheremail2 = $value->temail;
echo $teacheremail2;
}
hope this help

PHP loop not performing as it should

$query = "SELECT * FROM table WHERE data = '$userinput'";
$row = mysql_query($query);
while ($row = mysql_fetch_array($row))
{
echo $row['data'];
}
Ok So my questions are:
What exactly does mysql_fetch_array return?
AND if my WHERE clause finds multiple matches, shouldn't the loop execute numerous times?
I am running a program and I can only get the first result to print
You're overwriting $row. Instead use a different variable for the query result.
$query = "SELECT * FROM table WHERE data = '$userinput'";
$result = mysql_query($query);
while ($row = mysql_fetch_array($result))
{
echo $row['data'];
}
Try using mysql_fetch_assoc($row)
You should not use the same variable as the index and the loop variable.
$row = mysql_query
while( $row = ...
Replace the first $row with $result

Echo single MySQL field

I want to echo out one field from my database so I do not want to use a while loop.
The database table is called index and the field that I want to echo is called title.
What is wrong with this code as the output is just blank.
$result = mysql_query("SELECT * FROM index");
$row = mysql_fetch_array($sql);
echo $row['title'];
You're passing a wrong argument to mysql_fetch_array(). Modify it as follows.
$result = mysql_query("SELECT * FROM index");
$row = mysql_fetch_array($result);
echo $row['title'];
You need to pass $result and not $sql with the mysql_fetch_array()function.
Try:
$row = mysql_fetch_array($result);
print_r($row); ///see what you get
The fastest solution would be mysql_result
$result = mysql_query('SELECT title FROM index LIMIT 1');
$field = mysql_result($result, 'title');
You may want to add LIMIT or check your database against something
$result = mysql_query("SELECT * FROM index WHERE id='$someid' LIMIT 1");

sql query working in phpmyadmin but not via mysql_query in php

Well first of all I am French so I hope my question will be understandable ;-)
I know some people have already experienced problems with queries in php that worked in phpmyadmin. The thing is that each time (or so) these people had "echo" their queries and copy/paste in phpmyadmin, but as php does not always display spaces it was always the problem.
Actually my problem is different :
if I use the query
$sql = "SELECT * FROM jos_dtregister_invoice_sent";
$query = mysql_query($sql);
$result = mysql_fetch_array($query);
it returns all the rows in both phpmyadmin and my php code, but if I want to look in a different table (with same structure), it just works in phpmyadmin and not via my php code (only one row instead of all of them)
Here is the query not working:
$sql = "SELECT * FROM jos_dtregister_receipt_sent";
$query = mysql_query($sql);
$result = mysql_fetch_array($query);
Perhaps the answer is very simple but I admit this is kind of tricky for me...
Many thanks in advance!
Here is my complete code :
function sendReceipt($row) {
$to = getUserInformation($row,10);
$from = getEventAdminEmailFromEmail($row);
$subject = getEventTitle($row)." - Invoice #".$row["confirmNum"];
$message = $row["userFirstName"]." ".$row["userLastName"]." \n\n".getMessageToSendUser($row);
$headers = "From: ".$from."\r\n";
$sql1 = "SELECT * FROM `jos_dtregister_invoice_sent`";
$query1 = mysql_query($sql1);
echo 'Fetched rows number: '.mysql_num_rows($query1)."<br />";
while($row1 = mysql_fetch_array($query1)) {
echo "Invoice Sent: ".$row1["sent"]."<br />";
}
$sql2 = "SELECT * FROM `jos_dtregister_receipt_sent`";
$query2 = mysql_query($sql2);
echo 'Fetched rows number: '.mysql_num_rows($query2)."<br />";
while($row2 = mysql_fetch_array($query2)) {
echo "Receipt Sent: ".$row2["sent"]."<br />";
}
}
mysql_fetch_array() fetches only a row.The name suggests that it fetches a result row as an array
$sql = "SELECT * FROM jos_dtregister_receipt_sent";
$query = mysql_query($sql) or die(mysql_error());
$result = mysql_fetch_array($query);
Try to execute this. The mysql_error() line will spit out what exactly went wrong when trying to execute the SQL. Post it back here and we can help you a little more.
$sql = "SELECT * FROM jos_dtregister_receipt_sent";
$result = mysql_query($sql);
while($row = mysql_fetch_assoc($result)){
// $row will have your data
}
You need to loop over the results with mysql_fetch_array().
while ($result = mysql_fetch_array($query)) {
print_r($result);
}
Or if you want all your results in one big array ($results):
$results = array();
while ($row = mysql_fetch_array($query)) {
$results[] = $row;
}

How to display MySQL Select statement results in PHP

I have the following code and it should return just one value (id) from mysql table. The following code doesnt work. How can I output it without creating arrays and all this stuff, just a simple output of one value.
$query = "SELECT id FROM users_entity WHERE username = 'Admin' ";
$result = map_query($query);
echo $result;
I do something like this:
<?php
$data = mysql_fetch_object($result);
echo $data->foo();
?>
You have to do some form of object creation. There's no real way around that.
You can try:
$query = "SELECT id FROM users_entity WHERE username = 'Admin' ";
//$result = map_query($query);
//echo $result;
$result = mysql_query($query); // run the query and get the result object.
if (!$result) { // check for errors.
echo 'Could not run query: ' . mysql_error();
exit;
}
$row = mysql_fetch_row($result); // get the single row.
echo $row['id']; // display the value.
all you have is a resource, you would still have to make it construct a result array if you want the output.
Check out ADO if you want to write less.
Not sure I exactly understood, what you want, but you could just do
$result = mysql_query('SELECT id FROM table WHERE area = "foo" LIMIT 1');
list($data) = mysql_fetch_assoc($result);
if you wish to execute only one row you can do like this.
$query = "SELECT id FROM users_entity WHERE username = 'Admin' ";
$result = mysql_query($query);
$row = mysql_fetch_row($result);
echo $row[0];
there have been many ways as answered above and this is just my simple example. it will echo the first row that have been executed, you can also use another option like limit clause to do the same result as answered by others above.

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