Build and change a database

READ & UNDERSTAND

For a first load into an empty one-to-one target, source rows should equal loaded rows plus excluded rows. Count all three independently. Computing excluded as source minus loaded guarantees the equation balances even when the load silently lost a valid row.

A reconciliation needs row-level evidence as well as totals. Trail Gear records one decision for every staging row. Compare accepted serials with loaded serials and inspect changed field values. Equal counts do not prove equal identities or correct amounts.

For appends, deduplication, bridge expansion or unpivoting, one source row may not map to one target row. Document the mapping and the appropriate units. The simple equation here applies to this fresh fixed-fixture load; it is not a universal import formula.

SELECT decision, COUNT(*) AS rows FROM load_audit GROUP BY decision ORDER BY decision;

Your question

Return one row with source_rows from stg_items, loaded_rows from items, and excluded_rows counted from load_audit where decision is Excluded.

Explain your evidence

Could a balanced count hide the wrong serial or rate? Name an additional comparison that would expose it.

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