What is a Schema ?
A Schema is a collection of certain database objects such as tables, index , and views, all of which owned by a user account.
You can think of schema as being the same thing as user account, but there is a little difference b/w them.
user account houses the object own by a user and schema is a set of objects housed therein.
Definition you will find in a oracle documentation - "logical collection of database objects".
Ideally a "schema" should not be a random collection of objects, but the fact that there is nothing built into oracle that prevents user from doing that- randomly collecting objects into a user account.
A user account should be seen and used as logical collection of database objects,driven by business rules,collected into one organized entity- the schema.
A Schema has the same name as the user account. But it entirely possible to create a schema whose owner is not a human being at all, but perhaps a background application.
Schema and Non-Schema Objects ?
All database objects fall into 2 category or types.
"Schema" objects are those objects own by a user account.
"Non-schema" objects cannot owned by user account.
For example, USER is non-schema objects .Think about it, how can a user account own itself.
Schema Objects Non-Schema Objects
Tables Users
Constraints Roles
Indexes Public Synonyms
Views
Sequence
Private Synonyms
user account houses the object own by a user and schema is a set of objects housed therein.
Definition you will find in a oracle documentation - "logical collection of database objects".
Ideally a "schema" should not be a random collection of objects, but the fact that there is nothing built into oracle that prevents user from doing that- randomly collecting objects into a user account.
A user account should be seen and used as logical collection of database objects,driven by business rules,collected into one organized entity- the schema.
A Schema has the same name as the user account. But it entirely possible to create a schema whose owner is not a human being at all, but perhaps a background application.
Schema and Non-Schema Objects ?
All database objects fall into 2 category or types.
- Schema
- Non-Schema
"Schema" objects are those objects own by a user account.
"Non-schema" objects cannot owned by user account.
For example, USER is non-schema objects .Think about it, how can a user account own itself.
Schema Objects Non-Schema Objects
Tables Users
Constraints Roles
Indexes Public Synonyms
Views
Sequence
Private Synonyms
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