bug: explicit txn is not handled properly in mysql handler

[dantengsky]

Summary

explicit txn is not handled properly in mysql handler. (http handler/bendsql work as expected)

how to reproduce:

create or replace database poc2;
use poc2;


create or replace table poc2.t_1 (str varchar);
begin;
insert into poc2.t_1 (str) values ('a'), ('b');
select 1/0;
commit;
select * from poc2.t_1; // <- expects empty resultset

mysql hander fails the above test:

mysql> create or replace database poc2;
Query OK, 0 rows affected (0.20 sec)

mysql> use poc2;
Database changed
mysql>
mysql>
mysql> create or replace table poc2.t_1 (str varchar);
Query OK, 0 rows affected (0.12 sec)

mysql> begin;
Query OK, 0 rows affected (0.03 sec)

mysql> insert into poc2.t_1 (str) values ('a'), ('b');
Query OK, 2 rows affected (0.21 sec)

mysql> select 1/0;
ERROR 1105 (HY000): BadArguments. Code: 1006, Text = error:
  --> SQL:1:9
  |
1 | select 1/0
  |         ^ divided by zero while evaluating function `divide(1, 0)`

.
mysql> commit;
Query OK, 0 rows affected (0.08 sec)

mysql> select * from poc2.t_1;
+------+
| str  |
+------+
| a    |
| b    |
+------+
2 rows in set (0.17 sec)
Read 2 rows, 27.00 B in 0.036 sec., 56.2 rows/sec., 758.76 B/sec.

bendsql(http) ok:

root@localhost:8000/poc2> create or replace database poc2;

CREATE
OR REPLACE DATABASE poc2

root@localhost:8000/poc2> use poc2;


USE poc2

root@localhost:8000/poc2> create or replace table poc2.t_1 (str varchar);


CREATE
OR REPLACE TABLE poc2.t_1 (str varchar)

root@localhost:8000/poc2> begin;

BEGIN

root@localhost:8000/poc2> insert into poc2.t_1 (str) values ('a'), ('b');

INSERT INTO
  poc2.t_1 (str)
VALUES
  ('a'),
  ('b')

root@localhost:8000/poc2> select 1/0;
error: APIError: ResponseError with 1006: divided by zero while evaluating function `divide(1, 0)`
root@localhost:8000/poc2> commit;

COMMIT

root@localhost:8000/poc2> select * from poc2.t_1;

SELECT
  *
FROM
  poc2.t_1

0 row read in 0.073 sec. Processed 0 row, 0 B (0 row/s, 0 B/s)