Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b6caf1b909bd3974f26121f313bd2c279e87e65282c51eb5a7de764d6e2cec62' 
  AND token = 'g/RTX7sGK6cdknv6OX2kHScyB50Wy3p0MM2rZq5gkFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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