SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e8be151b98983c1b7c0702863a251d3ba5b939dbe369fc0994e71a732a59294' 
  AND token = 'eyRuDesrX7yERILHRjzGoMwC6X8PnmBRwNdtsk4k7jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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