转换科学计数法的数值字符串为decimal类型的方法

select cast('0.12' as decimal(18,2));
select convert(decimal(18,2), '0.12');

msg 8114, level 16, state 5, line 1
error converting data type varchar to numeric.
 
select cast('0.12e+006' as decimal(18,2));
select convert(decimal(18,2), '0.12e+006');

select cast(cast(1234400000 as float) as varchar)
1.2344e+009