Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fe755519b008e0b04701875990c64d4036de67ca0a7690077dede7938eefe989' 
  AND token = 'jvuDrHx9ckXoZEodfOuBpyaMWfenGUa3YKjts/PfwSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}