update test007 set c2=0;
update test007 set c2=1;
update test007 set c2=0;
update test007 set c2=1;
update test007 set c2=0;
update test007 set c2=1;
update test007 set c2=0;
update test007 set c2=1;
update test007 set c2=0;
update test007 set c2=1;