The Vanishing Three Legs Mystery

[Raybaudi]

Where are the legs ?

[Ender]

Is this some sort of riddle? :qwery:

[Raybaudi]

Yes !

I wish to know in wich case the relationship:

1) has 3 legs (---------E

2) has one I- (---------|

3) has one - (----------

and if there are other symbols

[LaRetta]

Daniele, the ones with the flat end signify either global field or unstored calculation. It means data will not flow through that direction. Straight line is standard single field connection and the fork (which varies slightly) indicates an added complexity in the relationship (more than one field, Allow Creation checked etc) but that data will flow through it, ie, it is indexed or can be indexed. So there are really two states ... data will flow or it will not. :wink2:

Edited January 6, 2006 by Guest
Clarified statement about single line vs. fork

[Ender]

As LaRetta says, the T indicates a global or unstored calc.

But a crow's foot indicates a possible "many" side (meaning the key is indexed.) and a straight connection indicates a "one" side of a relationship (meaning the key is defined to be unique or an auto-entered serial.)

In your diagram, the relationship would be useless because both sides have a T.

[Raybaudi]

Thank you LaRetta and Ender.

So, if I set a global as the key of the relationship, I'll see the T meaning that the relationship would be useless.

But why the Help On Line says:

"Notes

Container fields, summary fields, and calculations returning a container field as a result cannot be used as match fields.

The match fields used in a relationship can have different names.

[color:red]A match field can be a global field."

[LaRetta]

Match field on the LEFT side (parent) can be global or unstored.

Rephrased ... If you want data to flow into the parent from a related table, the match fields in the related table must be indexed. This is basic principle which really hasn't changed ...

Edited January 6, 2006 by Guest
Rephrased

[Raybaudi]

Ahh !

Many thanks LaRetta !