SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4edc16aad449611a513c5f7b87e7a9fa85543a083bb30cd9f6971f865d8c773d' 
  AND token = 'yO+OZzpJIG1WrB2ePpWYpiIAb/KT1q9lQ/kechN/n8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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