Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd7b5538782e3bacc99befdf4dfb436faaa56fd1ba13a5488a5cd1ba6ecbb92c' 
  AND token = 'UeT8fTyy1aCWsJqXxuV1Y/nqCEImX0G05S15CbTOnGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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