SELECT 
  processor_id 
FROM 
  cscart_payment_processors 
WHERE 
  processor = 'Affirm'

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_payment_processors",
      "access_type": "ALL",
      "rows": 77,
      "filtered": 100,
      "attached_condition": "cscart_payment_processors.processor = 'Affirm'"
    }
  }
}

Result