instruction: provide the number of patients whose admission year is less than 2124 and diagnoses long title is hemorrhage of gastrointestinal tract, unspecified?
response: SELECT COUNT(DISTINCT demographic.subject_id) FROM demographic INNER JOIN diagnoses ON demographic.hadm_id = diagnoses.hadm_id WHERE demographic.admityear < "2124" AND diagnoses.long_title = "Hemorrhage of gastrointestinal tract, unspecified"