Are tables and data files in Oracle Database the same thing?

Each database is made up of one or more tablespaces; Each tablespace is based on data files from one or more operating systems; Each tablespace can be stored in one or more segments; Each segment is made up of one or more segments; Each segment is made up of multiple contiguous oracle databases; Each oracle database is made up of one or more contiguous operating system databases; Each operating system data file is made up of one or more segments; Each operating system data file is made up of one or more operating system data blocks.

Segments can be stored across data files.

A simple partitioned table can know the answer, a partitioned table can correspond to multiple tablespaces, and a tablespace can correspond to multiple data files. So you can do that.

Not the same.

To put it simply, a database is a whole, and a database can protect multiple users, tables, stored procedures, jobs, and views.

A tablespace can be considered as a classification of data entity files, such as user tablespaces, system tablespaces, index tablespaces, etc., and a tablespace can protect multiple entity files.

You can set the storage size of a tablespace, but how much is actually used depends on the data that already exists.

For example, if you set the user tablespace to 10 GB, the storage device will allocate 10 GB to it. If there is already 2G of data in the tablespace, then you can also write 8G of data into it, but in this process, the tablespace only occupies 10G and will not increase, unless it is not enough after using up 10G, you need to increase it again.

Oracle and SQL are very different.

The oracle database must have a tablespace, if not specified, it is the default tablespace, you can understand that the tablespace is the place where things are stored in the database, and a tablespace can have multiple databases.

Hello A database is a place where data is stored, which can be understood as a warehouse, where some tables, stored procedures, triggers, and so on are placed.

A tablespace, on the other hand, simply brings some data together.

Logical relationships (from largest to smallest).

Database-User-Tablespace-Table-View-Triggers, Functions, Methods, etc.

An oracle tablespace is a collection of data files, while a database is a collection of objects, and a database contains many tablespaces, and tablespaces can only belong to one database.

An oracle database can have multiple instances (a generic database, usually one instance; Each database instance can have multiple tablespaces, multiple users can be created under each tablespace, and multiple tables, views, and methods can be created under each user.

Can such a logical relationship be understood?

Oracle tablespace is a virtual concept, tables are actually stored in data files, but data files can have more than one, in order not to care about which data file the table is actually stored in, so the concept of a tablespace is defined, combining one or more data files into a logical tablespace, the table must belong to a certain tablespace.

Tables and tablespaces are not the same concept, regardless of relational databases. As the name suggests, a table is where data is stored, and a tablespace is where you store this table.

A tablespace is a logical concept that consists of logical tables and physical data files.

The database name is the default orcl, you can also try to query, select name from v$database;

There is also a bit of a problem with the question you asked, you should have used the sqlserver database before, the oracle database permission control is different from the user, the database is an instance name orcl, and then there are different users that can be created below, these users are like the database in sqlserver! These users can then be assigned different permissions! So, you ask the user what is the name of the default database for the system user?

The default database name is the same for all users under Oracle! As long as the concept is separated from sqlserver, you will understand!

Segments are in a tablespace.

A segment is made up of a collection of zones.

A pane is a collection of data blocks.

Data blocks are mapped into disk blocks (OS blocks).

A zone is the smallest unit in which an oracle allocates space to a segment.

A block of data is the smallest unit of Oracle IO.

Whether a data block can store a table depends on the size of the table, and when the size of the table is less than the size of a block, it can be stored on a block.

Is it possible for a data block to store a table, and a table to occupy multiple data blocks?

Haha, don't worry too much about this question. Let me explain, I hope it helps you :

Data files and tablespaces are used to store data and are part of the database, but one is a physical concept and the other is a logical concept, and the physical concept is the files that you can see, such as all the files under the C disk of the Windows system, and the logical concept is not operable, only the operating system or the oracle itself can be seen. So you should be able to understand ...

The tablespace is the logical structure of the oracle database, all the database objects exist in the tablespace, and the tablespace depends on the physical structure of the data file, the physical file can be found at the operating system level, and the logical structure of the tablespace can only be found in the database.

A tablespace is just a logical concept. The actual data is still stored in physical files. To create a tablespace, you need to specify a physical file, which can be understood as the name of the physical file.

It's like if you create a word or excel. In fact, everyone is a document, but the name is different.

I'm happy to answer for you:

In Oracle, a user table can be stored in two data files. Because a table corresponds to a tablespace, and a tablespace can correspond to multiple data files, the relationship between a table and a data file is 1 to n.

Database: It's the software we installed, so I don't need to say much about it.

Example: The first step after installing the database is to create an instance, which is equivalent to the name of a large piece of land, for example, when you use PL SQL to connect to the database, the database name selected is actually the instance name, which is not rigorous. The configuration can be clearly seen in the file in the oracle installation path, which you should know, and then ask me if you don't know.

Tablespace: It's like a piece of land, and all your database objects are stored in the tablespace.

User: It is a login name, of course, you have to have a password, it is many-to-many relationship with the tablespace, but we generally specify the default tablespace when creating a user, if you do not specify the user's default tablespace, then the user has to specify the tablespace every time you create a database object, which is too troublesome.

Role: Each user has a role, which determines what permissions the user has, such as DBA, which has the highest permissions.

Table: Needless to say, it's important to note that a table can only belong to one tablespace.

I'm tired to death, and it's a bit hard to work without credit.

The landlord just wants to know the general meaning or dig deeper, and if you dig deeper, the landlord has to spend a lot of time on the database.

The following examples include data files, control files, archives, log files, etc.... An instance can only exist in one database at a time, whereas in the case of RAC, there can be multiple instances in a database.

User, as the name suggests, is a user who can log in to the database, only the permission, such as sysdba user has the permission to open the database and so on...

A tablespace is a kind of database logical structure, under which there are tables, segments, data blocks...

A table is a table that stores data files