SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '473484c277b4b6c0efdfe80918ba968dd8e9d4ba5b9dc1f8d7db965bf84a9009' 
  AND token = 'veQUv2E2Sb+Pudn1l8Emm7PQDemgdSe/6El9Rw3v7xA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}