SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13e254ab84bc8cf8f8ea16b51d4090ae4ab5cefa8679d0b7b3c77a108ef92cc1' 
  AND token = 'VShB/hNGE64+PcDO0VSnUj4Q94/JQeKcDXbmRgPrzqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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