MDEV-33470 Unique hash index is broken on DML for system-versioned table

Hash index is vcol-based wrapper (MDEV-371). row_end is added to
unique index. So when row_end is updated unique hash index must be
recalculated via vcol_update_fields(). DELETE did not update virtual
fields, so DELETE HISTORY was getting wrong hash value.

The fix does update_virtual_fields() on vers_update_end() so in every
case row_end is updated virtual fields are updated as well.

Author: midenok

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

@@ -224,3 +224,14 @@ ERROR HY000: The target table v1 of the DELETE is not updatable
 DROP VIEW v1;
 DROP TABLE t1;
 # End of 10.4 tests
+#
+# MDEV-33470 Unique hash index is broken on DML for system-versioned table
+#
+create or replace table t (
+c int, unique (c) using hash)
+with system versioning;
+insert into t values (0);
+delete from t;
+delete history from t;
+drop table t;
+# End of 10.5 tests

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

@@ -232,4 +232,17 @@ DROP TABLE t1;
 
 --echo # End of 10.4 tests
 
+--echo #
+--echo # MDEV-33470 Unique hash index is broken on DML for system-versioned table
+--echo #
+create or replace table t (
+  c int, unique (c) using hash)
+with system versioning;
+insert into t values (0);
+delete from t;
+delete history from t;
+drop table t;
+
+--echo # End of 10.5 tests
+
 --source suite/versioning/common_finish.inc

sql/sql_insert.cc

@@ -1810,10 +1810,6 @@ int vers_insert_history_row(TABLE *table)
   if (row_start->cmp(row_start->ptr, row_end->ptr) >= 0)
     return 0;
 
-  if (table->vfield &&
-      table->update_virtual_fields(table->file, VCOL_UPDATE_FOR_READ))
-    return HA_ERR_GENERIC;
-
   return table->file->ha_write_row(table->record[0]);
 }
 

sql/table.cc

@@ -9078,6 +9078,8 @@ void TABLE::vers_update_end()
                                         in_use->query_start_sec_part()))
     DBUG_ASSERT(0);
   vers_end_field()->set_has_explicit_value();
+  if (vfield)
+    update_virtual_fields(file, VCOL_UPDATE_FOR_WRITE);
 }
 
 /**