"Unknown database type json requested, Doctrine\DBAL\Platforms\MySQL57Platform may not support it." while running php artisan migrate command

try this solution may be this will work for you,

public function __construct()
{
    DB::getDoctrineSchemaManager()->getDatabasePlatform()->registerDoctrineTypeMapping('json', 'text');
}

For further reading about this issue check Issue #15772 at laravel repo


If you found this question at google, but your case is Symfony, but not Laravel - this is an answer.

Had same issue: Unknown database type json requested, Doctrine\DBAL\Platforms\MySqlPlatform may not support it. at Symfony/Sylius.

The reason - I had serverVersion=5.5 rather than serverVersion=5.7 at my app's .env file, when doctrine 2.6+ was installed by composer.

So right DATABASE_URL will be: DATABASE_URL=mysql://[email protected]/database_%kernel.environment%?serverVersion=5.7