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na1774

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January 11, 2012 at 10:24 pm

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Can any one explain me the difference between an Entity and an object

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na1774 SSCrazy Points: 2301 More actions · Answer 1

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When I read abt a schema. Its was saying that it is a colection of objects.

What r a the objects a schema may contain? It doe not make sense to say that it will contain DBs? Only thing that makes sense to me is a Schema may be considered as collection of tables. So according to def when he says objects does he mean to say that only tables?

Lynn Pettis SSC Guru Points: 442467 More actions · Answer 2

A schema may contain more than just tables. It could also have views, stored procedures, functions, synonyms, and other database objects.

PaulB-TheOneAndOnly SSC Guru Points: 66772 More actions · Answer 3

nawaz1774 (1/11/2012)
Can any one explain me the difference between an Entity and an object

You find Entities at ER modeling time - when you identify the entities and relationships of your system - please note that at this point you do not have a database.

You find objects as a result of the phisical implementation of your ER model, ER model will mostly help you design your tables and basic navigation (Referential Integirty based indexes). On top of those objects you will find a myriad of other objecs as already pointed by other poster, including but not limited to triggers, procedures, views... etc. In short, anything that has a name on the catalog is an object.

_____________________________________
Pablo (Paul) Berzukov

Author of Understanding Database Administration available at Amazon and other bookstores.

Disclaimer: Advice is provided to the best of my knowledge but no implicit or explicit warranties are provided. Since the advisor explicitly encourages testing any and all suggestions on a test non-production environment advisor should not held liable or responsible for any actions taken based on the given advice.

Lowell SSC Guru Points: 323518 More actions · Answer 4

i like to use a company and contact as examples.

a Company is an entity.

a table describing that entity, might include fields for the name, address, website and more.

then an employee of that same company would e an Entity or sub-entity.

from that i might develop a table that describes the employee's attributes: name, start date, date of birth, contact email, and stuff like that.

Lowell

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