#406 (Relations) Multiple merged foreign keys

If you have a linked table where there can be multiple
entries, then you cannot actually link the two tables
together if you want to add more than one id - the
dropdown list is a single-entry type. Instead could SET
fields pointing at another table have a multiple-choice
list that you can select from (keeping in mind that the
SET values might not include all entries from the
target table).

[Garvin Hicking]

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Can you please be more verbose/specific in your bug report?

If you say, that the linked table can have multiple entries:
Do you mean that you don't have the unique primary key set
as the 'connecting' factor?

Please check if your bug report is related to any one of
those feature requests:

#551702, #574858, #607812, #650357, #772988, #825505

Thanks,
Garvin.

[Anonymous]

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Checked out those feature requests, although one or two come
close, they're not quite what I mean.

Here's an example. tb_person is a list of animals, tb_hair
is a list of hair types, tb_person->hair is a SET (ie,
multiple entries) as someone can have "LONG" & "BLOND" hair.
Rather than putting the entries directly into the SET
values, have the SET point to the primary key of tb_hair,
which in turn contains the entries "LONG" and "BLOND".

For a normal linked table where you can only have a single
value it works perfectly as the Insert screen allows you to
select a single entry from a drop-down list. However, in a
SET type where there may be multiple entries, you still only
get the single drop-down list, and no way of adding more
than one entry.

Instead it should be a normal list, where you can
toggle-select one or more entries from the target table.

Is that any help?

[Garvin Hicking]

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Thanks, now I get it.

However, this is not the usual 1:1 relation we use for
primary key associations, and is more a feature request than
a bug.

I also think, this somehow doesn't fit into a foreign key
setup, and I guess InnoDB doesn't provide such foreign keys
as well, but we'd have to look into that.

I will move this to Feature Requests and hope, some others
may elaborate on this; I'm sure I have read of a 1-to-many
feature request somewhere already...

Regards,
Garvin.

[Anonymous]

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Well, the bug itself is that it's getting the drop-down
(single-item) list on a SET type, having a multi-select list
is a feature request though ;-)

[Garvin Hicking]

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It's not really a bug, that you get the dropdown for a SET
type. It's rather the whole idea, that we currently only
support 1-1 relations. And as I mentioned, I don't even know
if foreign key relations from a fixed SET column are
possible in MySQL/InnoDB. At least, it screws up your
relational integrity a lot. :-)

[Marc Delisle]

The team is not sure about this, but would appreciate sample tables.

[Marc Delisle]

No news, closing.