SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33bcc6b5b7103c68ae1d6535cb3e6b09788b5e3b390761e7628e285e58168c93' 
  AND token = 'I8uJzUVdbJpbeSbOD46PHhSvBJ6Pog7gqfSliUR4ZnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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