Скачать или смотреть Calculate Total Temp Size in Oracle Databases: A Compatible Solution for All Versions

Discover how to calculate the `total temporary size` efficiently across various Oracle database versions using a dynamic SQL query without encountering compatibility issues.
---
This video is based on the question https://stackoverflow.com/q/76532419/ asked by the user 'Roshni Rabi' ( https://stackoverflow.com/u/20087400/ ) and on the answer https://stackoverflow.com/a/76552301/ provided by the user 'Jon Heller' ( https://stackoverflow.com/u/409172/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: query to calculate total temp size in Oracle that works for all versions

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Calculate Total Temp Size in Oracle Databases Across Versions

When working with Oracle databases, especially in environments using multiple versions, you're likely to encounter compatibility issues when executing SQL commands designed for newer versions. One common challenge is calculating the total temporary space used across different databases, particularly when some versions may not support certain system views. In this guide, we will explore a solution that provides compatibility across various versions of Oracle databases, including 11g, 12c, and 19c.

The Problem

The issue arises when attempting to calculate the total temporary space in an Oracle database using a query that references CDB_TEMP_FILES. This view exists in container databases introduced with Oracle 12c, which means that if we reference it in a query on an older version, such as Oracle 11g, it will result in an error stating that the view does not exist. Thus, a solution is needed to ensure compatibility across all versions.

Here's the initial query that works well in environments with a container database:

[[See Video to Reveal this Text or Code Snippet]]

While effective on newer databases, this query fails on older versions. We need a strategy that dynamically adjusts based on the available views in the database.

The Solution

The most robust solution for querying across different versions of Oracle databases involves using the DBMS_XMLGEN package. This approach allows you to build a dynamic SQL statement based on what views are present in the current database, thus avoiding compatibility errors. Here’s how to do it step by step.

Step-by-step Breakdown

Create the Dynamic SQL Statement:

Based on the available views in the database, we generate a SQL statement that sums the temporary space, either from DBA_TEMP_FILES or CDB_TEMP_FILES, depending on which ones exist.

Convert SQL Result to XML:

Once the SQL statement is generated, we convert the result to XML format. This ensures that the result can be processed cleanly and consistently, regardless of the underlying database version.

Extract the Total Size from XML:

Finally, we use XMLTABLE to extract the necessary value from the XML output, getting the total temporary size in gigabytes.

The Final Query

Here is the complete solution wrapped into a single query:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By structuring your SQL query to dynamically adapt based on the available database views, you can effectively calculate the total temporary size across various versions of Oracle databases. This method is not only efficient but also scalable should future versions introduce additional changes to how temporary files are managed. Now you'll be able to seamlessly retrieve this information without worrying about compatibility issues, making your database management efforts much smoother.

Feel free to reach out if you have further questions or need assistance with Oracle SQL queries!