insert into transaction_schema (schema_type, schema_version, schema)
values 
(
    'payment', 
    '1.0.0', 
    '{"type": "object", "required": ["amount", "currency"], "properties": {"amount": {"type": "number"}, "currency": {"type": "string"}}}'
),
(
    'refund', 
    '1.0.0', 
    '{"type": "object", "required": ["original_txn_id"], "properties": {"original_txn_id": {"type": "string"}}}'
);