SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '018825a076dcd6006fe581b39eec30aaf130165fee2dda2f3d0f8725bc575e5a' 
  AND token = 'rUGFLvM8mUQqZxSQsOpowIURpqY3Ow9qp00iEScDRRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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