SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4b2f6c325ce001044700fd6b646ffc635fbef9fdfe614827aa6bf19abcb96be0' 
  AND token = 'JoorLDGJpG/J2/oD2MResBZa9nTQbBYhSvKAahmlJoU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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