SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbcb824d57ea26c5521785eadebf5d1fe979330c6e1f5f43821b395499d80e58' 
  AND token = 'z2a8ne58IthLyhrVFzU/4OHPQEvbEcJtNsVZXKi/FY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}