presto-mysql/src/main/java/io/prestosql/plugin/mysql/MySqlClient.java/MySqlClient/listSchemas
class MySqlClient:    @Override
    protected Collection<String> listSchemas(Connection connection)
    {
        // for MySQL, we need to list catalogs instead of schemas
        try (ResultSet resultSet = connection.getMetaData().getCatalogs()) {
            ImmutableSet.Builder<String> schemaNames = ImmutableSet.builder();
            while (resultSet.next()) {
                String schemaName = resultSet.getString("TABLE_CAT");
                // skip internal schemas
                if (!schemaName.equalsIgnoreCase("information_schema") && !schemaName.equalsIgnoreCase("mysql")) {
                    schemaNames.add(schemaName);
                }
            }
            return schemaNames.build();
        }
        catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }