-- Snowflake version: Check dispensing by VMP (Virtual Medicinal Product)
-- Uses GPMeds dispensing data from NATIONAL.GPMED

WITH SnomedCodes AS (
    SELECT "ProductSnomedCode"
    FROM DATA_HUB.DWH."DimMedicineAndDevice"
    WHERE "MedicinalLatestSnomedCode" = '40326811000001109'  -- Specific VMP
),
LatestPeriod AS (
    SELECT MAX("ProcessingPeriodDate") AS MaxPeriodDate
    FROM NATIONAL.GPMED."MedicinesDispensedInPrimarycare"
)
SELECT
    gpm."ProcessingPeriodDate",
    dos."OrganisationName",
    COUNT(DISTINCT gpm."PatientPseudonym") AS UniquePatientCount,
    SUM(gpm."ItemCount") AS TotalItemsDispensed,
    SUM(gpm."PaidQuantity") AS TotalQuantityDispensed
FROM NATIONAL.GPMED."MedicinesDispensedInPrimarycare" gpm
INNER JOIN SnomedCodes sc ON gpm."PaiddmdCode" = sc."ProductSnomedCode"
LEFT JOIN DATA_HUB.DWH."DimOrganisationAndSite" dos
    ON gpm."CostCentreODSCode" = dos."SiteCode"
CROSS JOIN LatestPeriod lp
WHERE gpm."ProcessingPeriodDate" > DATEADD(MONTH, -12, lp.MaxPeriodDate)
    AND gpm."ProcessingPeriodDate" <= lp.MaxPeriodDate
GROUP BY gpm."ProcessingPeriodDate", dos."OrganisationName", gpm."CostCentreODSCode"
ORDER BY gpm."ProcessingPeriodDate", dos."OrganisationName";