SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'efa2762481ac0770cc339683e8b949ada18975ca4a1d3d84ebb1e36e2b40a079' 
  AND token = 'y/8TrAiKe15BzaMnfozfHw/J9L167R+CRgwyNJ866UQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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