core.medical_claim has no diagnosis columns — normalized_code and
principal_diagnosis_code live in core.condition. Added two staging steps
that enrich claims before measure functions consume them:
- _stg_medical_claim: LEFT JOIN rank-1 condition for principal_diagnosis_code
- _stg_medical_claim_condition: INNER JOIN all conditions for MCC cohort matching
Updated uamcc_int_mcc_cohort, uamcc_int_planned_admission,
uamcc_int_outcome_exclusion, and uamcc_int_numerator to consume
the staging tables instead of raw core.medical_claim.
b2a7a0b037
