SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3058d874e2bd5f03da27f5630033091d76e81e0c792e0528c665155f0526678a' 
  AND token = '9Q+b5qVrbTPlAsFLtAftq69qLt/jYPAK2A+NaPttJFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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