for this you would use the DataAssist Manage Relational Table behavior on the insert and update pages.
start by running the DataAssist to create the pages to manage the main table.
after the pages are created, you will need to create a recordset to query the table that contains the available options to return the option ID and Option name.
Add a checkbox to the page, set the label to use the option Name column from your recordset, and set the value of the checkbox to use the ID column, for example:
<?php echo $row_recordsetName['NameColumn']; ?><input name="options" type="checkbox" id="options" value="<?php echo $row_recordsetName['IDColumn']; ?>">
then add a repeat region around the checkbox to loop through the option recordset.
you will need to add the recordset and checkboxes as outlined above on both the insert and update pages.
now, for the insert page:
open the server behaviors tab, and double click the Insert Record behavior. Make sure that the insert does not have a redirect set, if it does, remove the redirect. Then look in the Save inserted ID as a Session Section, and make note of the Store As setting, this is the session that will save the ID. Click cancel to close the insert behavior, then open the bidings panel, expand the session collection and make sure there is a binding there with the same name from the Store As section of the Insert behavior. If not, you will need to create one: Click the plus button and select Session Variable, use the name from the Store As section of the Insert behavior.
now go back to the server behaviors panel, click the plus button and select WebAssist -> DataAssist -> Manage Relational Table.
On the First screen select the relational table.
On the next screen select the column that relates to the main table, click the lightning bolt for Value and select the session that is created by the insert behavior.
On the next screen select the column that relates to the option table the options form field should already be set to use your checkbox.
the final screen allows to double check the setting before clicking finish.
On the update page, the steps for applying the MRT behavior will be very similar with one major difference:
The update page uses a Querystring variable to set which record to update.
open the update page in a browser to update a record and make note of the address in the address bar, especially the Querystring variable, for example:
the query string variable name in this example is:
On the bindings panel, expand the URL Section and make sure there is a binding of the same name. If not, create one: Click the plus button, select URL Variable and use the name from your address bar.
in the second screen of the manage relations table behavior where you select the column that relates to the main table, click the lightning bolt for Value and select the URL Variable. all of the other settings will be the same on the update page.