SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7869cedf943c3412c497940977cf2048afa3977d486dbd879e037e5af67461a5' 
  AND token = 'Z59APysq/2kQIj8xgUar3ukyREQXus8IlrCgg/zpejQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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