--disable_warnings
drop table if exists t1, t2 ;
--enable_warnings
create table t1 ( my_test varchar(100), my_col longtext) ;

## here comes the insert causing the strange result
set @arg00=1.0;
insert into t1 set my_test= 'non PS, 1.0 in parameter',my_col = @arg00 ;

# Some logically similar commands
prepare stmt1 from "insert into t1 set my_test='PS,1.0 in parameter',my_col=?";
execute stmt1 using @arg00 ;
insert into t1 set my_test= 'non PS, 1.0 as constant',my_col=1.0;
prepare stmt1 from "insert into t1 set my_test='PS,1.0 as constant',my_col=1.0";
execute stmt1 ;
select my_test, my_col from t1 ;

# Why do I beleave that @arg00 is treated as DOUBLE ?
create table t2 as select 1.0 as my_const, @arg00 as my_param ;
show create table t2 ;