Are there any potential performance issues with using ORDER BY RAND() in MySQL queries with PHP?
Using ORDER BY RAND() in MySQL queries can cause performance issues, especially with large datasets, as it requires MySQL to generate a random number for each row in the table before sorting them. This can be inefficient and slow down the query execution time. One way to solve this issue is to use a different method to randomize the results, such as selecting a random offset or using a hash function.
// Using a random offset to select random rows efficiently
$query = "SELECT * FROM table_name ORDER BY id LIMIT 10 OFFSET " . rand(0, $total_rows - 10);
$result = mysqli_query($connection, $query);
// Loop through the results
while($row = mysqli_fetch_assoc($result)) {
// Process each row
}
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