It's possible to modify the xml generated in menu item in this :
<?xml version="1.0" encoding="utf-8"?>
<metadata>
<layout title="TITLE" option="View">
<message>
<![CDATA[DESC]]>
</message>
</layout>
<fields name="params">
<fieldset
name="basic"
label="LABEL">
<field
name="item_id"
query="SELECT null as id UNION SELECT `id` FROM #__mycomp_table ORDER BY `id`"
type="sql"
key_field="id"
value_field="id"
label="LABEL"
require="true"
description="JGLOBAL_SHOW_TITLE_DESC">
</field>
</fieldset>
</fields>
</metadata>
So we can create "hidden" menu voices and override the id creating custom link with the id..
Example:
index.php?option=mycom&view=myview&id=12&Itemid=123
without the Union select the componet will ignore the id=12 and use every time the id specified in the menu.