SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db2274d195e31698014e5ebb77c587428ecd7fc10a5a0ee9c191a79ba8e21d91' 
  AND token = 'VoJ/CyZslfBRC4J8IIkNnmdznaTjMi8Mx2dkmXuw2XI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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