SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4e13ded4447ab4e77401fb49f4c42f1744b003f5cc2520fbdc858a8714d6ec7' 
  AND token = 'clwxUWKEjUdMMRFNKLg8T6BcQIop/QXcI/dUvSCsLsY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}