Relationship Clarification & Loading records

[djc728]

Hello all:

I have a general question regarding relationships. If you have Table 1 thats related to Table 2 as a one to many and then Table 3 is related to Table 2 as a one to many.

My question is when do the records load from the sub tables or in this case Table 2 and Table 3. So for instance if I have a layout and I'm loading a record from Table 1 -- do the records from Table 2 and Table 3 load as well because of the relationship? I guess I'm wanting to know is when do records load in general. If Table 1 can pull records from Table 3 because of the relationship then I'm assuming that if I put 2 portals on a layout for Table 1 -- one portal for table 2 recs and 1 portal for Table 3 recs that I will be able to view those records which makes me believe that records load from all tables that are related upon the layout being displayed or is it a case of the records are available but will not be loaded unless you have an object like a portal on the layout to actually display those records.

Dom

[comment]

I am not sure what you mean by "load". In general, Filemaker is a lazy application: it does everything on 'as needed' basis. For example, if you have an unstored calculation field, and the field is NOT on the current layout, the calculation will not be evaluated.

In addition, data from related records ("join results") is kept in a cache. That is sometimes a problem, since the developer and Filemaker may not always agree on when the cache needs to be flushed.

[djc728]

By 'load' I mean are the records stored in memory. I guess it becomes an issue say if you have a table with say, just for arguments sake, 10,000 related records. If you display a portal are those 10,000 records cached in memory AND are any tables related to those tables cached in memory. I guess it all comes down to having FIND scripts that will reduce the number of records cached.

[comment]

I don't know what FM stores in memory. I am guessing not a lot, since if you have a lot of records in a portal, the scrolling can get slow.