MDEV-23644 Assertion on evaluating foreign referential action for self-reference in system versioned table

First part of the fix (row0mysql.cc) addresses external columns when adding history row on referential action. The full data must be retrieved before the row is inserted. Second part of the fix (the rest) avoids duplicate primary key error between the history row generated on referential action and the history row generated by SQL command. Both command and referential action can happen on same table since foreign key can be self-reference (parent and child tables are same). Moreover, the self-reference can refer multiple rows when the key is non-unique. In such case history is generated by referential action occured on first row but processed all rows by a matched key. The second round is when the next row is processed by a command but history already exists. In such case we check TRX_ID of existing history row and if it is the same we assume the above situation and skip adding one more history row or failing the command.

Author: midenok

mysql-test/suite/versioning/common.inc

@@ -70,6 +70,11 @@ returns int
 deterministic
  return sys_trx_end = $sys_datatype_max;
 
+eval create or replace function current_row_ts(sys_trx_end timestamp(6))
+returns int
+deterministic
+ return convert_tz(sys_trx_end, '+00:00', @@time_zone) = TIMESTAMP'2038-01-19 03:14:07.999999';
+
 delimiter ~~;
 eval create or replace function check_row(row_start $sys_datatype_expl, row_end $sys_datatype_expl)
 returns varchar(255)
@@ -86,4 +91,20 @@ begin
 end~~
 delimiter ;~~
 
+delimiter ~~;
+eval create or replace function check_row_ts(row_start timestamp(6), row_end timestamp(6))
+returns varchar(255)
+deterministic
+begin
+ if row_end < row_start then
+ return "ERROR: row_end < row_start";
+ elseif row_end = row_start then
+ return "ERROR: row_end == row_start";
+ elseif current_row_ts(row_end) then
+ return "CURRENT ROW";
+ end if;
+ return "HISTORICAL ROW";
+end~~
+delimiter ;~~
+
 --enable_query_log

mysql-test/suite/versioning/common_finish.inc

@@ -4,5 +4,7 @@ drop procedure if exists verify_trt;
 drop procedure if exists verify_trt_dummy;
 drop function if exists current_row;
 drop function if exists check_row;
+drop function if exists current_row_ts;
+drop function if exists check_row_ts;
 --enable_warnings
 --enable_query_log

mysql-test/suite/versioning/r/delete.result

@@ -138,13 +138,13 @@ f1 int, f2 text, f3 int, fulltext (f2), key(f1), key(f3),
 foreign key r (f3) references t1 (f1) on delete set null)
 with system versioning engine innodb;
 insert into t1 values (1, repeat('a', 8193), 1), (1, repeat('b', 8193), 1);
-select f1, f3, check_row(row_start, row_end) from t1;
-f1	f3check_row(row_start, row_end)
+select f1, f3, check_row_ts(row_start, row_end) from t1;
+f1	f3check_row_ts(row_start, row_end)
 1	1	CURRENT ROW
 1	1	CURRENT ROW
 delete from t1;
-select f1, f3, check_row(row_start, row_end) from t1 for system_time all;
-f1	f3check_row(row_start, row_end)
+select f1, f3, check_row_ts(row_start, row_end) from t1 for system_time all;
+f1	f3check_row_ts(row_start, row_end)
 1	1	HISTORICAL ROW
 1	NULL	ERROR: row_end == row_start
 1	1	HISTORICAL ROW

mysql-test/suite/versioning/r/foreign.result

@@ -398,6 +398,8 @@ Warning	1265	Data truncated for column 'f12' at row 7
 SET timestamp = 9;
 REPLACE INTO t2 SELECT * FROM t2;
 DROP TABLE t1, t2;
+set timestamp= default;
+set time_zone='+00:00';
 #
 # MDEV-16210 FK constraints on versioned tables use historical rows, which may cause constraint violation
 #
@@ -427,3 +429,17 @@ insert into t2 values (1), (1);
 # DELETE from foreign table is allowed
 delete from t2;
 drop tables t2, t1;
+#
+# MDEV-23644 Assertion on evaluating foreign referential action for self-reference in system versioned table
+#
+create table t1 (pk int primary key, f1 int,f2 int, f3 text,
+key(f1), fulltext(f3), key(f3(10)),
+foreign key (f2) references t1 (f1) on delete set null
+) engine=innodb with system versioning;
+insert into t1 values (1, 8, 8, 'SHORT'), (2, 8, 8, repeat('LONG', 8071));
+delete from t1;
+select pk, f1, f2, left(f3, 4), check_row_ts(row_start, row_end) from t1 for system_time all order by pk;
+pk	f1	f2	left(f3, 4)	check_row_ts(row_start, row_end)
+1	8	8	SHOR	HISTORICAL ROW
+2	8	8	LONG	HISTORICAL ROW
+drop table t1;

mysql-test/suite/versioning/r/trx_id.result

@@ -5,7 +5,15 @@ sys_trx_start bigint(20) unsigned as row start invisible,
 sys_trx_end bigint(20) unsigned as row end invisible,
 period for system_time (sys_trx_start, sys_trx_end)
 ) with system versioning;
+# No history inside the transaction
+start transaction;
 insert into t1 (x) values (1);
+update t1 set x= x + 1;
+update t1 set x= x + 1;
+commit;
+select *, sys_trx_start > 1, sys_trx_end from t1 for system_time all;
+x	sys_trx_start > 1	sys_trx_end
+3	1	18446744073709551615
 # ALTER ADD SYSTEM VERSIONING should write to mysql.transaction_registry
 set @@system_versioning_alter_history=keep;
 create or replace table t1 (x int);

mysql-test/suite/versioning/t/delete.test

@@ -102,9 +102,9 @@ create table t1 (
  foreign key r (f3) references t1 (f1) on delete set null)
 with system versioning engine innodb;
 insert into t1 values (1, repeat('a', 8193), 1), (1, repeat('b', 8193), 1);
-select f1, f3, check_row(row_start, row_end) from t1;
+select f1, f3, check_row_ts(row_start, row_end) from t1;
 delete from t1;
-select f1, f3, check_row(row_start, row_end) from t1 for system_time all;
+select f1, f3, check_row_ts(row_start, row_end) from t1 for system_time all;
 
 # cleanup
 drop table t1;

mysql-test/suite/versioning/t/foreign.test

@@ -421,6 +421,8 @@ REPLACE INTO t2 SELECT * FROM t2;
 
 # Cleanup
 DROP TABLE t1, t2;
+set timestamp= default;
+set time_zone='+00:00';
 --let $datadir= `select @@datadir`
 --remove_file $datadir/test/t1.data
 --remove_file $datadir/test/t1.data.2
@@ -458,4 +460,20 @@ insert into t2 values (1), (1);
 delete from t2;
 drop tables t2, t1;
 
+--echo #
+--echo # MDEV-23644 Assertion on evaluating foreign referential action for self-reference in system versioned table
+--echo #
+create table t1 (pk int primary key, f1 int,f2 int, f3 text,
+ key(f1), fulltext(f3), key(f3(10)),
+ foreign key (f2) references t1 (f1) on delete set null
+) engine=innodb with system versioning;
+
+insert into t1 values (1, 8, 8, 'SHORT'), (2, 8, 8, repeat('LONG', 8071));
+
+delete from t1;
+select pk, f1, f2, left(f3, 4), check_row_ts(row_start, row_end) from t1 for system_time all order by pk;
+
+# cleanup
+drop table t1;
+
 --source suite/versioning/common_finish.inc

mysql-test/suite/versioning/t/trx_id.test

@@ -14,7 +14,13 @@ create or replace table t1 (
  period for system_time (sys_trx_start, sys_trx_end)
 ) with system versioning;
 
+--echo # No history inside the transaction
+start transaction;
 insert into t1 (x) values (1);
+update t1 set x= x + 1;
+update t1 set x= x + 1;
+commit;
+select *, sys_trx_start > 1, sys_trx_end from t1 for system_time all;
 
 --echo # ALTER ADD SYSTEM VERSIONING should write to mysql.transaction_registry
 set @@system_versioning_alter_history=keep;

sql/sql_delete.cc

@@ -246,7 +246,15 @@ int TABLE::delete_row()
 
  store_record(this, record[1]);
  vers_update_end();
- return file->ha_update_row(record[1], record[0]);
+ int err= file->ha_update_row(record[1], record[0]);
+ /*
+ MDEV-23644: we get HA_ERR_FOREIGN_DUPLICATE_KEY iff we already got history
+ row with same trx_id which is the result of foreign key action, so we
+ don't need one more history row.
+ */
+ if (err == HA_ERR_FOREIGN_DUPLICATE_KEY)
+ return file->ha_delete_row(record[0]);
+ return err;
 }
 
 

storage/innobase/data/data0data.cc

@@ -738,7 +738,7 @@ void
 dtuple_convert_back_big_rec(
 /*========================*/
 dict_index_t*	index MY_ATTRIBUTE((unused)),/*!< in: index */
-dtuple_t*	entry,/*!< in: entry whose data was put to vector */
+dtuple_t*	entry,/*!< in/out: entry whose data was put to vector */
 big_rec_t*	vector)/*!< in, own: big rec vector; it is
 freed in this function */
 {