Talk:Weak entity

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I wish some body could post some examples for weak entity types... i am bored of seeing Employee-Has-Dependent example all my life...

Yes I can't even see that point of a wek entity - don't they contridict the relational model if they can't be identified by their attributesw - when are they ever necessary ?

Weak entities don't have to be ID-dependent!

I don't have time to edit the page right now, but a weak entity does not have to be ID-dependent. That is, an entity may depend on the presence of another entity without needing to have that other entity's primary key as part of its primary key. For example, if there are the entities HOUSE and HOUSE_TYPE, the entity HOUSE is weak because it cannot exist without being a certain type of house. However, it may be simply identified by its address. See David M. Kroenke's Database Processing published by Prentice Hall.

I disagree: Weak entities have to be ID-dependent!

If you read C.J. Date, you will find that the only tables that *matter* are tables involved in identifying relationships. Type tables represent normalization, but have non-identifying relationships and are thus not relevant to the issue of weak entities —The preceding unsigned comment was added by 65.96.171.108 (talk) 07:50, 4 February 2007 (UTC).[reply]

What of strong entities?

I think there should be a page on strong entities. —The preceding unsigned comment was added by 62.10.85.111 (talk) 13:48, 31 December 2006 (UTC).[reply]

Too confusing...

I just need to point out that, as someone with relative, but not great, familiary with relational databases, I find that the following paragraph from the article makes zero sense. I don't want to remove it, because it might be essential, but could someone who does understand it please clarify it? Thanks. 96.224.44.230 15:27, 11 July 2007 (UTC)[reply]

Need Image

This article need an image displaying the notation used for weak entity in popular notations and how it's used in a model. — Preceding unsigned comment added by 110.175.240.90 (talk) 22:42, 3 September 2011 (UTC)[reply]

Overly complicated E-R diagram

Weak entities are to be demonstrated, but it's full of "bloat" in a sense. For example, CustomerName is enought to prove a point, whereas CustomerAddress serves no explanatory purpose but rather makes it take more time to process the diagram. Perhaps a smaller, straight to the point diagram would make the article better.. the current one could be there as an "another example" or something. — Preceding unsigned comment added by 83.250.191.58 (talk) 21:05, 19 February 2014 (UTC)[reply]