KADB锁冲突查看及解决

begin;

update data_table set addr='test' where id=89;

alter table data_table add test varchar(20);

test=# select pid,waiting,waiting_reason,query from pg_stat_activity;

 pid  | waiting | waiting_reason | query                             

------+---------+----------------+----------------------------------------------------------------

 3059 | t       | lock           | alter table data_table add test varchar(20);

 3055 | f       |               | update data_table set addr='test' where id=89;

 4295 | f       |            | select pid,waiting,waiting_reason,query from pg_stat_activity;

(3 rows)

test=# select database,relation from pg_locks where pid=3059;

 database | relation

----------+----------

    18097 |    18334

(2 rows)

test=# select pid from pg_locks where relation=18334;

 pid 

------

 3059

 3055

 3055

 3222

 3222

 3223

 3223

test=# select query from pg_stat_activity where pid in (3222,3055,3223);

                     query                     

------------------------------------------------

 update data_table set addr='test' where id=89;

(1 row)

test=# select * from gp_toolkit.gp_locks_on_relation where lorrelname like '%data_table%';

 lorlocktype | lordatabase | lorrelname | lorrelation | lortransaction | lorpid |       lormode       | lorgranted |                lorcurrentque

ry                

-------------+-------------+------------+-------------+----------------+--------+---------------------+------------+--------

 relation    |       18097 | data_table |       18334 |                |   3059 | AccessExclusiveLock | f          | alter table data_table add t

est varchar(20);

 relation    |       18097 | data_table |       18334 |                |   3055 | AccessShareLock     | t          | update data_table set addr='

test' where id=89;

 relation    |       18097 | data_table |       18334 |                |   3055 | ExclusiveLock       | t          | update data_table set addr='

test' where id=89;

(3 rows)

test=# select pg_terminate_backend('3055');

 pg_terminate_backend

----------------------

 t

(1 row)