Do it like shown below:DELETE FROM tbl_PatientVisitsWHERE post_date BETWEEN CONVERT(DATETIME, '2013-02-01', 120) AND CONVERT(DATETIME, '2013-02-28', 120)
Even better, in case someone provides the date that includes a time portion (and if the variable/column had enough width to support it), would be to have it like this:DELETE FROM tbl_PatientVisitsWHERE post_date >= CONVERT(DATETIME, '2013-02-01', 120) AND post_date < DATEADD(dd,1,CONVERT(DATETIME, '2013-02-28', 120) )