SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eebd000ac72776ea65d91bb4cdb96617a005dc97ebe3c3284e7907f140f0cdd' 
  AND token = 'QIzHfc6PC3kGIn1d3VWKHZWZ85+yAFnF3tktuibUys4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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