cleanup

pipeline = [{$unset: [
    'abuse',
    'accessories',
    'adverse_reactions_table',
    'adverse_reactions',
    'animal_pharmacology_and_or_toxicology',
    'animal_pharmacology_and_or_toxicology_table',
    'ask_doctor_or_pharmacist',
    "ask_doctor_or_pharmacist_table",
    'ask_doctor',
    'boxed_warning',
    'boxed_warning_table',
    'carcinogenesis_and_mutagenesis_and_impairment_of_fertility_table',
    'carcinogenesis_and_mutagenesis_and_impairment_of_fertility',
    'cleaning',
    'clinical_pharmacology_table',
    'clinical_pharmacology',
    'clinical_studies',
    'components',
    'contraindications',
    'contraindications_table',
    'controlled_substance',
    'dependence',
    'disposal_and_waste_handling',
    'do_not_use',
    'dosage_and_administration',
    'dosage_forms_and_strengths',
    'dosage_forms_and_strengths_table',
    'drug_abuse_and_dependence',
    'drug_and_or_laboratory_test_interactions',
    'drug_and_or_laboratory_test_interactions_table',
    'drug_interactions',
    'drug_interactions_table',
    'general_precautions',
    'general_precautions_table',
    'geriatric_use',
    'geriatric_use_table',
    "health_care_provider_letter",
    "health_care_provider_letter_table",
    'how_supplied',
    'inactive_ingredient',
    'indications_and_usage',
    'information_for_patients',
    'information_for_owners_or_caregivers',
    'information_for_owners_or_caregivers_table',
    'instructions_for_use',
    'intended_use_of_the_device',
    'keep_out_of_reach_of_children',
    'labor_and_delivery',
    'laboratory_tests',
    'mechanism_of_action',
    'mechanism_of_action_table',
    'microbiology',
    'nonclinical_toxicology',
    "nonclinical_toxicology_table",
    'nonteratogenic_effects',
    'nursing_mothers',
    'other_safety_information',
    'overdosage',
    'overdosage_table',
    'package_label_principal_display_panel',
    'patient_medication_information',
    'patient_medication_information_table',
    'pediatric_use',
    'pediatric_use_table',
    'pharmacodynamics',
    'pharmacodynamics_table',
    'pharmacogenomics',
    'pharmacokinetics_table',
    'pharmacokinetics',
    'precautions',
    'precautions_table',
    'pregnancy_or_breast_feeding',
    'pregnancy',
    'pregnancy_table',
    'questions',
    'questions_table',
    'recent_major_changes',
    'recent_major_changes_table',
    'references',
    'references_table',
    'risks',
    'route',
    'safe_handling_warning',
    'set_id',
    'spl_indexing_data_elements',
    'spl_medguide_table',
    'spl_medguide',
    'spl_patient_package_insert_table',
    'spl_patient_package_insert',
    'spl_product_data_elements',
    'spl_unclassified_section_table',
    'spl_unclassified_section',
    'stop_use',
    'stop_use_table',
    'storage_and_handling',
    'storage_and_handling_table',
    'teratogenic_effects',
    'use_in_specific_populations',
    'use_in_specific_populations_table',
    'user_safety_warnings',
    'warnings_and_cautions_table',
    'warnings_and_cautions',
    'warnings',
    'warnings_table',
    'when_using'
   ]}, {$merge: {
    into: 'drug_data',
    on: '_id',
    whenMatched: 'replace'
   }}];
   db.drug_data.aggregate(pipeline,  { allowDiskUse: true });