mysql - 如何将此 Simple SQLServer 语句转换为 MySQL 语句？

Question

给定一个包含 3 列的表：C1、C2、C3

C1 - C2 - C3
M - 是 - M1
N2 - 是 - N3
M2 - 是 - M3
M3 - 是 - M4
N1 - 是 - N2
M1 - 是 - M2
N - 是 - N1

如何将此 Simple SQLServer 语句转换为 MySQL 语句：

declare @searchString varchar(32) = 'M';
with cte(results) as
(
    select C3 from Tbl where C1 = @searchString
    union all
    select t.C3 from Tbl t inner join cte c on c.C3 = t.C1 
) select * from cte;