SQL SELECT statement error with datetime -

something wrong statements datetime field:

mydb:

id  name   datetime 1   test1  2011-04-28 19:37:44 2   test2  2011-04-28 21:27:04 

when run following statement

select *  mytable  ('datetime' > '2011-04-28 21:00:00') 

i - test1 , test2

when run statement

select *  mytable  ('datetime' = '2011-04-28 21:27:04') 

i nothing

when run following statement

select *  mytable  ('datetime' > '2011-04-28 21:00:00')     , ('datetime' < '2011-04-29 21:00:00') 

i nothing

why?

you putting field name "datetime" quotes , mysql treats string, not column.

select * mytable datetime > '2011-04-28 21:00:00';