SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddcca4c86737ae00ae61ed32e7c042171d8a7f916620019622974ff057ffba10' 
  AND token = 'indLB68SYzKkPeyXGfKsftSfLMFNV08ph8X5wd1r2WE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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