How to check if a table is being used in oracle

Even this approach has some pitfalls but should be good enough for most requirements. The approach is limited by the policies you set for AWR repository. So testtest and validate every approach as every application is different. Tagged: How to check whether oracle stored procedure is being usedHow to check whether Oracle table is being usedHow to check whether stored procedure is being usedHow to check whether table or index is being usedprocedureunsed procedure.

With this approach you are creating your own history tables manually. Thanks thats good info… I have another question, can we know how many times that object index being used by application in perticular time frame.

So test and validate every approach as every application is different. Index Monitoring : Tried and Trusted method. You are commenting using your WordPress. You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. TwelveC Oracle12c And Beyond. Most PopularOracle June 3, Comments: 8. So testtest and validate every approach as every application is different thanks.

Share this: Twitter Facebook. Like this: Like Loading Yusuf June 17, at am Reply. Thanksexcellent info. Any idea how to do this in a standard edition? TimPhillsen December 1, at pm Reply.Index usage tracking in Oracle This article is essentially a rewrite of the previous Index Monitoring article, bringing it in line with Oracle Database 12c Release 2 The database maintains all indexes defined against a table regardless of their usage.

With this in mind, it makes sense to identify and remove any indexes that are not being used as they are a pointless drain on resources. Index usage tracking allows unused indexes to be identified, helping to removing the risks associated with dropping useful indexes.

It is important to make sure that index usage tracking is performed over a representative time period. If you only check index usage during specific time frame you may incorrectly highlight indexes as being unused. The safest method is to use a tracking period which spans the whole lifecycle of your application, including any OLTP and batch operations. Before we continue it is important to mention the impact of sampling on index usage tracking.

By default index usage is sampled, rather than tracking all index usage. When I first wrote this article I was having trouble getting the index usage tracking views to notice my tests.

The sampling approach is likely to notice the index usage in a normal running system, where indexes are repeatedly being accessed, but it can easily miss indexes used for one-off tests like those in this article. I Googled and found a post by Franck Pachot who mentioned the following switch to control the statistics collection type.

For the rest of this article I will have this parameter set to "ALL" for the session, so the results you see will be consistent. I would not suggest this on a live system unless you've tested and are happy with the overhead.

Also keep this in mind when you are trying to decide if an index is unused. Is it really unused, or has the index usage tracking just not noticed its use? The columns of the view are described in full herebut here are some that standout. The columns are described here. In addition to the basic usage information there are columns representing usage histograms to give a little more information on the type of usage. Remember, you will have to wait for a flush before this view will contain information.In Oracle The database maintains all indexes defined against a table regardless of their usage.

With this in mind, it makes sense to identify and remove any indexes that are not being used as they are a pointless drain on resources.

how to check if a table is being used in oracle

Index monitoring allows unused indexes to be identified accurately, removing the risks associated with dropping useful indexes. It is important to make sure that index monitoring is performed over a representative time period. If you only monitor indexes during specific time frames you may incorrectly highlight indexes as being unused. The safest method is to use a monitoring period which spans the whole lifecycle of your application, including any OLTP and batch operations. If you are using a version prior to Oracle From Oracle When a foreign key is unindexed, DML on the parent primary key results in a share row exclusive table lock or share-subexclusive table lock, SSX on the child table, preventing DML from other transactions against the child table.

If the DML affects several rows in the parent table, the lock on the child table is obtained and released immediately for each row in turn. When a foreign key is indexed, DML on the parent primary key results in a row share table lock or subshare table lock, SS on the child table.

This type of lock prevents other transactions from issuing whole table locks on the child table, but does not block DML on either the parent or the child table. Only the rows relating to the parent primary key are locked in the child table. This issue is mitigated somewhat in later releases, but it is still worth considering, and above all testing. Index monitoring is only a guideline and does not list all indexes used by the system. Prior to Oracle Once the statement runs, other indexes for recursive SQL, like constraint checking, will also be referenced, but may not be included in the object usage views.

Use index monitoring as a guide line, not an absolute. As mentioned previously, the monitoring is only as good as the sample period you observe.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. It only takes a minute to sign up. I am an Oracle DBA. Application owner is asking me when was the last time Oracle database was accessed? How do I find information about the DB usage timeline?

I mean, I want to check whether it is being used by the application or not? Unfortunately the application owner has no idea whether her application is used by the users or not. From DBA's side which data dictionary should I look into? Can ASH help? Take a look at it this thread on AskTom :.

Auditing is the right answer, funny thing with auditing - we only really want it when it isn't on don't we :.

how to check if a table is being used in oracle

If you don't have any database internal mechanisms like auditing in place, you could also look at the listener log. What do you know about the application? Sometimes the easiest way is to grep listener.

SQL Error ORA-00942 Table or View Does Not Exist in Oracle Database

Auditing is automatically turned on for logons and logoffs. You can query this DBA view and get when users logged on or off. This would tell you if somebody accessed the database. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Ask Question. Asked 5 years, 2 months ago. Active 5 years, 2 months ago. Viewed 8k times. Jack says try topanswers. Pratik Mehta Pratik Mehta 11 1 1 silver badge 3 3 bronze badges. What version of Oracle do you have?

Answer to this question may be very different by this kind of question : are all of the application objects isolated into a separate DB schema, or are they placed all over the database? Active Oldest Votes. Marcos Marcos 2 2 bronze badges.October 26, by Kenneth Fisher. After some research I found the system table syscomments.

This has a few problems. First ABC could be listed in the comments and not in any real code. Microsoft added the system view sys. The code I used in SQL was as follows:. The field sys. This means that SQL stores long pieces of code in a single row instead multiple.

This DMV returns any object that references the object you pass it. While either of the older two pieces of code will still work there is a big advantage to using the DMV. Table1 and SchemaB. Table1 are two different objects after all. Next we need to look at any code that is referenced by the SP. Not a big deal in this example but in a multi page SP it could get a bit trickier. The easiest way to get a list of all of the code called by an object or trigger is to use the system SP sys.

Side note: there is also a system sp sys. Unfortunately I think object level is as far as you can get. You are commenting using your WordPress. You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. This site uses Akismet to reduce spam. Learn how your comment data is processed.

RSS - Posts.

how to check if a table is being used in oracle

RSS - Comments. Like this: Like Loading January 7, at AM. April 15, at AM.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. The dark mode beta is finally here.

Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I'm also checking if this answer can help me in any way. Learn more. How to identify all stored procedures refering a particular table in Oracle Ask Question. Asked 3 years, 1 month ago. Active 3 years, 1 month ago.

Join the world’s largest interactive community dedicated to Oracle technologies.

Viewed 9k times. I will appreciate any assistance. Binyamin Regev Binyamin Regev 1 1 gold badge 10 10 silver badges 25 25 bronze badges. Active Oldest Votes. MT0 MT0 Also, it would be good if you use admin user login which. Normal user may not have access to list the dependencies. This solution will not list the stored sub programs where the table is referred in dynamic SQL. Sign up or log in Sign up using Google.

Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Featured on Meta. Community and Moderator guidelines for escalating issues via new response…. Feedback on Q2 Community Roadmap.

Index Usage Tracking (DBA_INDEX_USAGE, V$INDEX_USAGE_INFO) in Oracle Database 12c Release 2 (12.2)

Technical site integration observational experiment live on Stack Overflow.Why is Oracle not using my index? First, we need to know a few details about your optimizer settings:.

In sum, the Oracle optimizer should immediately see a new index and begin using it immediately, invalidating all SQL that might benefit from the index. When Oracle does not use an index, you can force him to use the index with diagnostic tools.

Testing to force Oracle to use an index is easy. The "best" query for response time is usually the one that fetches the rows with the fewest consistent gets. These are ONLY testing tools, but you will still need to find the reason my Oracle is ignoring your index and not using the index in your query. Burleson is the American Team Note: This Oracle documentation was created as a support and Oracle training reference for use by our DBA performance tuning consulting professionals.

Feel free to ask questions on our Oracle forum. Verify experience! Anyone considering using the services of an Oracle support expert should independently investigate their credentials and experience, and not rely on advertisements and self-proclaimed expertise. All legitimate Oracle experts publish their Oracle qualifications. Oracle technology is changing and we strive to update our BC Oracle support information.

If you find an error or have a suggestion for improving our content, we would appreciate your feedback. All rights reserved by Burleson. This will also re-analyze the indexes on the target table. If you suspect a bug and you are in a test environment you can also issue the " alter system flush shared pool " command to re-initialize all SQL.

Forcing Oracle to use an index When Oracle does not use an index, you can force him to use the index with diagnostic tools. Search BC Oracle Sites.


comments

Leave a Reply

Your email address will not be published. Required fields are marked *