Hello Ilan

You can use placeholders in URL, for example.com/%VAR1%/, and then add some value to Var1, and it will be applied for this URL.

Also, you can use other placeholders, like %CURRENT_USER_ID% and in that way, only the data based on the ID of the currently logged-in user would be displayed.

You can use placeholders as predefined filtering values for string-type columns, but the user cannot select the value which will be forwarded to the placeholders in JSON URL. The only thing you can do is create a custom form on some page, and forward values from the input as POST variables on some page, where this table is; then through a hook wpdatatables_before_get_table_metadata replace it with placeholders var1, var2, or var3, which will be forwarded to the URL.

API needs to return the JSON format, adjusted to wpDataTables.