Added Db::beforeExecuting() to register a hook which to be run just before a database query is executed.

[huangdijia]

Db::beforeExecuting(function($query, $bindings, $connection) {
    // your logic
});

Example:

Db::beforeExecuting(function($query, $bindings, $connection) {
    if (Str::startsWith($query->sql, 'delete') && !Str::contains($query->sql, 'where')) {
        throw new Exception('Lost the condition!');
    }
});