Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a746903095d923b0f2ddff9fe2ca41cd3a70066efb678e5ea2329208d7d9ccd' 
  AND token = 'D1jt0AOHRDSlrYujPOfLNpgSYpvDNJlluVLnOliCewc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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