Description:
Execute a statement with secondary engine, there are two entries in performance schema.
In sql_parse.cc
static void check_secondary_engine_statement(), when statement is restarted in another storage engine the performance schema end the last statement and start a statement again. This make a statement with secondary engine will have two or more entries in performance schema.
```
1460 // Tell performance schema that the statement is restarted.
1461 MYSQL_END_STATEMENT(thd->m_statement_psi, thd->get_stmt_da());
1462 thd->m_statement_psi = MYSQL_START_STATEMENT(
1463 &thd->m_statement_state, com_statement_info[thd->get_command()].m_key,
1464 thd->db().str, thd->db().length, thd->charset(), nullptr);
```
How to repeat:
Add testcase in mysql-test/suite/secondary_engine/t/
secondary_engine_performance.test
./mtr secondary_engine.secondary_engine_performance
```
--disable_query_log
eval INSTALL PLUGIN mock SONAME '$MOCK_PLUGIN';
--enable_query_log
CREATE TABLE t1(id INT PRIMARY KEY, x INT, y INT);
INSERT INTO t1 VALUES (1, 2, 3), (4, 5, 6), (7, 8, 9);
ALTER TABLE t1 SECONDARY_ENGINE MOCK;
ALTER TABLE t1 SECONDARY_LOAD;
SELECT * FROM t1;
select SOURCE, SQL_TEXT, DIGEST from performance_schema.events_statements_history_long where sql_text = "SELECT * FROM t1";
DROP TABLE t1;
--disable_query_log
UNINSTALL PLUGIN mock;
--enable_query_log
```
Result two entries in performance schema.
```
CREATE TABLE t1(id INT PRIMARY KEY, x INT, y INT);
INSERT INTO t1 VALUES (1, 2, 3), (4, 5, 6), (7, 8, 9);
ALTER TABLE t1 SECONDARY_ENGINE MOCK;
ALTER TABLE t1 SECONDARY_LOAD;
SELECT * FROM t1;
id x y
select SOURCE, SQL_TEXT, DIGEST from performance_schema.events_statements_history_long where sql_text = "SELECT * FROM t1";
SOURCE SQL_TEXT DIGEST
init_net_server_extension.cc:96 SELECT * FROM t1 533c0a9cf0cf92d2c26e7fe8821735eb4a72c409aaca24f9f281d137427bfa9a
sql_parse.cc:1464 SELECT * FROM t1 533c0a9cf0cf92d2c26e7fe8821735eb4a72c409aaca24f9f281d137427bfa9a
DROP TABLE t1;
```
Suggested fix:
Will one statement match one entry in performance schema better?
