SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31a020849d377e1ca5854b629606992062927f3cd538de127ebd11bb6901e1ae' 
  AND token = '+RY7B3Y6yurwVMagaR5zo3PbMAUQGhnQmiIUnD7XG8U=' 
  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"
    }
  }
}