SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '047520a0ce230a94891b3c687722e74f0012f7908a22ada3d32e86d12e410171' 
  AND token = 'iCV42MFtmjm9iYXOjjxdvZ66mP3zObhxfs5qBG2jAug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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