You didn't reference a schema in the example above.
If you created a database named "test_database". In the "test_database" database you can create schemas "test_database_schema_1", "test_database_schema_2", and "test_database_schema_3". In each of these schemas you can create tables "table_1", "table_2", and "table_3".
Now if user1 logged into the "test_database" database there would be three schemas each containing three tables.
Originally posted by Phillipe Rodrigues: From the above details does it mean that the all 3 schemas tables: contain different data,update or modification in particular schema's table will not reflect to other schemas.
Is it that use of schemas is to distinguish users for the tables?
Is it that a database has atleast one schema as default?
Do we create schema before or after database?
If you will have a correct answer, you need to tell us which database you want information about.
Oracle have e.g. databases (SIDs) which then have a number of schema (database users).
In regards to an Oracle database you are correct. Each of the table_1 tables in the different schemas could have the exact same table structure and contain different data. Also an insert, update, or deletion of data in one table will have no effect on the data in a table with the same name found in other schema. There is also nothing that says each of the table_1 tables have to have the same structure in the different schemas. One table could have 5 columns and another 8 columns.
If I am not mistaken every user has a schema, but I don�t think you have to have a user for each schema. Also just because a user has a schema doesn�t mean they can create a table in it.
Yes there are some default schemas and accounts. All schemas are created after the database except those default schemas of course. There are also schemas and accounts like scott you want to delete as soon as possible.
I asked around and it appears I was mistaken. Rene's correct in that one could characterize a schema as being synonymous with a user. The best way I can explain it from the people I asked about it is a schema is created when a user is created and the objects a user owns reside in their schema.
Do the next thing next. That’s a pretty good rule. Read the tiny ad, that’s a pretty good rule, too.