Well, that title may not fit exactly but here's the issue:  An FM file referenced as an external data source will not open on its own (in the parent file) until it is first referenced on a layout of the parent.  This reference could act from ANY calculation such as:  conditional formatting, tooltip, hide, merge variables, custom menu calcs ... there are MANY ways calculations can exist on a layout.  

 

So any calculation which references another file from the current layout will open the second file.  But I did not expect this to open a second file ...

 

For a changelog process, I am capturing schema at startup and then at close, comparing it to produce a list of only deleted, added and changed tables/fields.  I was using:

ExecuteSQL ( 
"SELECT 
    TableName,
     FieldName,
    ModCount
FROM FileMaker_Fields" 
; "" ; ""  )

I would have thought that only the parent file's information would be included but instead, if there is a table occurrence from your other file, it will include that information as well.  So setting a global variable with this calculation referenced the other file since it was in the graph and forced the data file to open.

 

I just thought others might be interested in my unexpected results.  It makes sense when you think about it but it was not as I would have expected.

For anyone interested or not yet aware of these hidden functions, here is a link:  

http://www.anvildataworks.com/?p=1251/

By using these links functions (but replacing with their internal unique Ids), we can leverage a powerful group of information dynamically for use in scripting as well as providing great changelogs. 

 

replaced 'links' with 'functions'

Edited September 3, 201411 yr by LaRetta