You will find couples of questions around requesting difference / explanation on determining and non-determining relationship in relationship database.
My real question is, are you able to think about a less complicated term of these jargons? I realize that terminology need to be specific and unambiguous though. But getting an 'alternative name' may help students relate easier towards the concept behind.
We really desire to use a far more layman term within our own database modeling tool, to ensure that first-time customers with little computer science background could learn faster.
I frequently see child table or dependent table used like a lay term. You could utilize either of individuals terms for any table by having an determining relationship
Then say a referencing table is really a table having a non-determining relationship.
PhoneNumbers is really a child of
Users, just because a telephone number comes with an determining relationship using its user (i.e. the main key of
PhoneNumbers features a foreign answer to the main key of
Users table includes a
state column that's an overseas answer to the
States table, which makes it a non-determining relationship. Which means you could say
States, however is not a young child from it by itself.
I believe goes to will be a good reputation for the determining relationship.
A "weak entity type" doesn't have its very own key, only a "partial key", so each entity demonstration of this weak entity type needs to fit in with another entity instance so it may be recognized, which is an "determining relationship". For instance, a landlord will have a database with flats and rooms. A room could be known as kitchen or bathroom, even though that title is exclusive inside an apartment, you will see many rooms within the database using the title kitchen, so it's really a partial key. To distinctively identify an area within the database, you have to say that it's the kitchen in this particular apartment. Quite simply, the rooms fit in with flats.
I am likely to recommend the word "weak entity" from ER modeling.
Some modelers conceptualize the topic matter to be comprised of organizations and associations among organizations. This brings about Entity-Relationship Modeling (ER Modeling). A characteristic could be associated with an entity or perhaps a relationship, and values saved within the database are cases of characteristics.
Should you choose ER modeling, there's a type of entity known as a "weak entity". Area of the identity of the weak entity may be the identity of the more powerful entity, that the weak one goes.
A good example may be a purchase within an order processing system. Orders comprise line products, and every line item consists of an item-id, one-cost, along with a quantity. But line products do not have an determining number across all orders. Rather, a line item is recognized by . Quite simply, a line item can't exist unless of course it's a part of exactly one order. Item # 1 may be the first item in whatever order it goes to, however, you need both amounts to recognize a product.
It's not hard to turn an ER model right into a relational model. It is also easy for those who are experts within the data but have no knowledge about databases to get accustomed to an ER type of the information they understand.
You will find other modelers who argue emphatically against the requirement for ER modeling. I am undertake and don't.
Nothing, practically nothing within the type of modeling where one encounters items like "associations" (ER, I presume) is "technical", "precise" or "unambiguous". Nor will it be.
A) ER modeling is definitely by necessity informal, since it can't ever be adequate to capture/express the whole meaning of a database.
B) You will find a wide variety of ER dialects available that it's just impossible its these to use the identical terms with the identical meaning. Lately, I even learned that some United kingdom college that shows ER modeling, uses the word "entity subtype" for the identical factor which i used title "entity supertype", and vice-versa !
You could use
You've Link between two tables, in which the IDs are identical.
That kind of factor.