wpdb in WordPress?<p><code>wpdb</code> is a WordPress class that helps you safely run database queries. It connects to the WordPress database and lets you get, insert, update, or delete data.</p>wpdb?You use the $wpdb->prepare() method. It replaces placeholders with safe values to avoid SQL injection.
Example: $wpdb->prepare('SELECT * FROM wp_posts WHERE ID = %d', $post_id);
wpdb method would you use to get a single row from the database?You use $wpdb->get_row(). It returns one row as an object, array, or associative array.
get_results() and get_var() in wpdb?get_results() returns multiple rows as an array of objects.
get_var() returns a single value from the database, like one cell.
prepare()?Directly inserting variables can cause SQL injection, a security risk where attackers can run harmful commands. prepare() safely escapes variables to prevent this.
wpdb method is used to safely insert data into the database?insert() is used to add new rows safely. prepare() helps build queries but does not insert data by itself.
prepare() for a string value?%s is for strings, %d is for integers, and %f is for floats.
wpdb method returns a single value from the database?get_var() returns one value, like a single cell from a table.
$wpdb->query() return after running an UPDATE statement?query() returns the number of rows changed by the statement.
wpdb->prepare() before running a query?prepare() escapes variables to keep the database safe from malicious input.
wpdb and retrieve multiple rows.get_row(), get_results(), and get_var() in wpdb.