SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e917c3f640a224c5f0d89e4c7d3be2f96426e1b47f4b8c079b909156fd628b3' 
  AND token = 'WcNpMSzeTh/6wVO8Ba+LguIYBGhWmbIDNGlXKcIDpvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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