Oracle table space size query skills and practice

Oracle table space size query skills and practice

In Oracle database management, table space is used to store database objects (such as tables, indexes, views, etc.) Logical structure is an important part of database management. Understanding the size of the table space is crucial for database administrators, which can help them adjust storage space in a timely manner and optimize database performance. This article will introduce some techniques for querying table space size and provide code examples to help readers better practice database management.

1. Query the total size and used space of table space

To query the total size and used space of each table space in the Oracle database, you can use the following SQL statement:

SELECT tablespace_name,
       SUM(bytes) AS total_space,
       SUM(bytes - (decode(autoextensible, 'YES', maxbytes, bytes))) AS used_space,
       SUM(decode(autoextensible, 'YES', bytes - maxbytes, 0)) AS free_space
  FROM dba_data_files
GROUP BY tablespace_name;

The above SQL statement will return the name, total size, used space and free space information of each table space. Through this information, you can clearly understand the storage status of each table space.

2. Query the size and usage of each data file in the table space

If you want to check the size and usage of each data file in each table space, you can use The following SQL statement:

SELECT tablespace_name,
       file_name,
       bytes AS total_size,
       bytes - (decode(autoextensible, 'YES', maxbytes, bytes)) AS used_space,
       decode(autoextensible, 'YES', bytes - maxbytes, 0) AS free_space
  FROM dba_data_files;

The above SQL statement will list the table space, file name, total size, used space and available space to which each data file belongs, helping administrators to monitor each data in more detail File storage status.

3. Query the table and index size of each data file in the table space

If you want to check the size of the table and index in each data file, you can use the following SQL statement:

SELECT tablespace_name,
       segment_type,
       SUM(bytes) AS segment_size
  FROM dba_segments
GROUP BY tablespace_name, segment_type;

The above SQL statement will return the size of different types of database objects (such as tables, indexes, etc.) in each table space, helping administrators understand the storage occupation of database objects in different table spaces. Condition.

Through the query techniques and code examples introduced above, readers can better understand the size of the Oracle database table space, adjust the storage space in a timely manner, and ensure the normal operation and performance optimization of the database. I hope this information can help database administrators and bring a better database management experience.

The above is the detailed content of Oracle table space size query skills and practice. For more information, please follow other related articles on the PHP Chinese website!