can you share your entire code please On Mon, Nov 19, 2018 at 4:03 PM 徐涛 <happydexu...@gmail.com> wrote:
> Hi Experts, > I use the following sql, and sink to mysql, > select > > album_id, date > count(1) > from > coupon_5_discount_date_conv > group by > album_id, date; > > > when sink to mysql, the following SQL is executed: insert into xxx (c1, > c2,c3) values (?,?,?) on duplicate key update c1=VALUES(c1),c2=VALUES(c2 > ), c3=VALUES(c3) > The engine is InnoDB, column c1,c2 is unique key, the isolation > level is READ COMMITTED. But in the log a deadlock exception happens. > As I know, because the unique key exists, only the line lock will be > applied, no gap lock will be applied. And due to a group by sentence, the > same unique key should be written by the same thread. So in this case, > why the dead lock should happened? Could anyone help me? Thanks a lot. > > Best > Henry >
