MDEV-28288 System versioning doesn't support correct work for

	   engine=connect and doesn't always give any warnings/errors

Disabled system versioning for connect due to unsupported
microseconds (MDEV-15967).

storage/connect/ha_connect.cc

@@ -6467,6 +6467,15 @@ int ha_connect::create(const char *name, TABLE *table_arg,
   PGLOBAL g= xp->g;
 
   DBUG_ENTER("ha_connect::create");
+
+  if (table_arg->versioned())
+  {
+    /* Due to microseconds not supported by CONNECT (MDEV-15967) system versioning
+       cannot work as expected (MDEV-15968, MDEV-28288) */
+    my_error(ER_VERS_NOT_SUPPORTED, MYF(0), "CONNECT storage engine");
+    DBUG_RETURN(HA_ERR_UNSUPPORTED);
+  }
+
   /*
     This assignment fixes test failures if some
     "ALTER TABLE t1 ADD KEY(a)" query exits on ER_ACCESS_DENIED_ERROR

storage/connect/mysql-test/connect/r/tbl.result

@@ -141,3 +141,12 @@ DROP TABLE t1;
 DROP TABLE t2;
 DROP TABLE t3;
 DROP TABLE t4;
+#
+# MDEV-28288 System versioning doesn't support correct work for
+#            engine=connect and doesn't always give any warnings/errors
+#
+create table t2 (
+x int,
+y int
+) engine=connect table_type=FIX file_name='test.txt' with system versioning;
+ERROR HY000: System-versioned tables do not support CONNECT storage engine

storage/connect/mysql-test/connect/t/tbl.test

@@ -51,3 +51,14 @@ DROP TABLE t1;
 DROP TABLE t2;
 DROP TABLE t3;
 DROP TABLE t4;
+
+
+--echo #
+--echo # MDEV-28288 System versioning doesn't support correct work for
+--echo #            engine=connect and doesn't always give any warnings/errors
+--echo #
+--error ER_VERS_NOT_SUPPORTED
+create table t2 (
+  x int,
+  y int
+) engine=connect table_type=FIX file_name='test.txt' with system versioning;