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mysqli_num_rows() expects parameter 1 to be mysqli_result, bool given in C:\laragon\www\studentfee\015proc_search2.php on line 25

What I have tried:


$searchterm= trim($searchterm);

if (!$searchtype || !$searchterm)
	echo ' Please Enter your search. Please enter again.';

include ('001link_db2.php');
$query = "select * from v_student_fee LIKE '%$searchterm'";
$result = mysqli_query($conn,$query);
$num_results = mysqli_num_rows($result);
echo "<center>";
echo '<p>The numbers: '.$num_results.'</p>';

<P><center> List</center>  
<table border="1" width="849" align="center" cellspacing="2" cellpadding="2">
<td align="center" bgcolor="#FFCC00">ID</td>
<td align="center" bgcolor="#FFCC00">Student Name</td>
<td align="center" bgcolor="#FFCC00">Total Fees</td>


for ($i=0; $i <$num_results; $i++)
 $row = mysqli_fetch_all($result);
 echo "<tr>";
 echo "<td>" .$row["id"]. "</td>";
 echo "<td>" .$row["student_name"].  "</td>";
 echo "<td>" .$row["total_fees"]."</td>";

echo "</table>";
echo "<center>";
echo "<br>";

Updated 9-Feb-22 9:05am

If you check the documentation for PHP: mysqli::query - Manual[^] you will clearly see that when the query statement fails the call returns the boolean value FALSE. Do not assume that your API calls always do what you think; check the return values first.
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Look at your SQL:
$query = "select * from v_student_fee LIKE '%$searchterm'";

There are two problems with it:
1) It's not valid SQL syntax.
2) It's very dangerous.

The syntax of a basic SELECT is simple:
SELECT * FROM MyTable WHERE MyColumn LIKE '%123'
Yours is missing the WHERE keyword, and the column name ... SQL will not "Guess what you mean", you have to explicitly tell it.

And never concatenate strings to build a SQL command. It leaves you wide open to accidental or deliberate SQL Injection attack which can destroy your entire database. Always use Parameterized queries instead.

When you concatenate strings, you cause problems because SQL receives commands like:
SELECT * FROM MyTable WHERE StreetAddress = 'Baker's Wood'
The quote the user added terminates the string as far as SQL is concerned and you get problems. But it could be worse. If I come along and type this instead: "x';DROP TABLE MyTable;--" Then SQL receives a very different command:
SELECT * FROM MyTable WHERE StreetAddress = 'x';DROP TABLE MyTable;--'
Which SQL sees as three separate commands:
SELECT * FROM MyTable WHERE StreetAddress = 'x';
A perfectly valid SELECT
A perfectly valid "delete the table" command
And everything else is a comment.
So it does: selects any matching rows, deletes the table from the DB, and ignores anything else.

So ALWAYS use parameterized queries! Or be prepared to restore your DB from backup frequently. You do take backups regularly, don't you?
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