How to execute simple SQL query in PHP?

Steps to execute SQL query in PHP: Connect to the database (mysqli_connect) Execute the query (mysqli_query) Get the query results (mysqli_fetch_assoc)

How to execute a simple query in PHP SQL Query

Executing simple SQL queries in PHP is very easy. First, you need to connect to the database. This can be done through the mysqli_connect() function, where the four parameters correspond to the database server, username, password and database name. For example:

$db_host = 'localhost';
$db_username = 'root';
$db_password = 'password';
$db_name = 'database_name';
$mysqli = mysqli_connect($db_host, $db_username, $db_password, $db_name);

After establishing a database connection, you can use the mysqli_query() function to execute SQL queries. This function takes the query string as its first parameter and the connection object as its second parameter. It returns a result object containing the query results, or FALSE if the query fails. For example:

$query = "SELECT * FROM users";
$result = mysqli_query($mysqli, $query);

The result object can be used to obtain query results. The most commonly used method is mysqli_fetch_assoc(), which returns the current row in the result object as an associative array. For example:

while ($row = mysqli_fetch_assoc($result)) {
  echo $row['name'] . '<br>';
}

This loop will print out the name column for each row in the query results.

Practical case

The following is a sample code to obtain all user records in the database:

You need to remember that users must be authenticated before executing SQL queries Input to prevent SQL injection attacks.

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