Oracle Performance Tuning - EXPLAIN PLAN

An overview of EXPLAIN PLAN feature of Oracle with demo on how to generate the plan and interpret the plan.

[@aakashteotia]

Excellent video. Just one video and I get an excellent overview of explain plan. Gonna watch other continuation videos as well.

[@nareshtamiri2891]

Very good explanation please upload more videos related to performance tuning

[@prakashchakravarthyg]

Excellent Explanation of Basics

[@sandeepgautam5241]

Thank you Saurabh...very helpful for me.

[@13eau33]

Thanks Saurabh! very practical

[@rakeshs3397]

Very good explanation Saurabh.. I am waiting for Access Methods video.:)

[@gautam26trivedi]

Good practical session please share a more practical video on performance tunning.

[@BewithuNnk]

Tq for upload. How to trace if it's a query getting slow with an explain plan and what are the steps to solveif find something

[@saurabh29101988]

Full table scan slows down query, create indexes. Also rewriting query helps.

[@BewithuNnk]

@@saurabh29101988 tq for responding, if already have indexes on those tables(shows TABLE FULL ACCESS under operation column) . How to overcome it. I created indexes on which columns used in joins & where conditions? Shall we create indexes whose column values contain null (not all rows)? And pls guide me if any other ways?

[@BewithuNnk]

@@saurabh29101988 actually what I'm looking is retrieving data from Excel through Data option from oracle server. This takes a long time.?

[@madhubabu8886]

Thank you for video ,I have a query with view ,that view made on joining two views ...select *from v1 where sno=123 like this taking too much time how to analysis query and how to improve that query performance

[@vipul7010]

Nice video... I came here from PL/SQL Developer Channel in Telegram... Will be looking forward for your more videos for in-depth analysis of the explain plan and please make more on Tuning as well....Keep up the great work and your explanation is really easy to understand.....

[@saurabh29101988]

thank you, will do my best.

[@abdulmannang]

Bhut telegram dekhte ho

[@vipul7010]

@@abdulmannang hahahaha you found me 😂

[@parmeshwarhippargi5817]

Please do create video on join method used in explain plan and access methods. Thanks

[@ashishchamoli2371]

Hi, this video is helpful for beginners. Will you be able to add a video mentioning how to read big explain plan for complex query. I mean from where to start reading explain plan and go on. Thank you

[@saurabh29101988]

Noted

[@ishankhan6143]

THNKS BHAI SMJH AAGYA

[@shashank2004]

Nice video,but can u explains more about the use of bytes and cost how it's calculated and how to tune the query?

[@saurabh29101988]

bytes depends on the no of records fetched and cost is just a number calculated as per cpu usage and io performed .

[@Parvej669]

Thank you for this great video:)

[@Philomathic_human]

Can you explain plan hash value? What is the purpose and how it works?

[@prabhatshrama5499]

Thanks Saurabh.

[@rajatchhabra189]

I am wondering what's the print on your T-Shirt seems odd as it doesn't give the full picture and may confuse people in the video ... I hope its Cup Cakes with Cherry Toppings... lol

[@saurabh29101988]

No its not cup cakes lol..its a victory✌ sign. Didnt expected this many people will view the video. Will have to be watchful next time. 🙂

[@marianfernandes]

In which scenario do we face “TABLE ACCESS BY ROWID”

[@saurabh29101988]

Every table has a pseudocolumn named rowid. It is the physical memory location. If oracle already has the rowids to filter record(probably from an index), it will go for TABLE ACCESS BY ROWID.

[@marianfernandes]

@@saurabh29101988 Thanks for the prompt reply. I have one last question and appreciate your time and patience to answer. What if the column im selecting is not indexed. Example : SELECT A,B from TAB where B=8; (Column B is not indexed) Is there a possibility that it will still give me a “TABLE ACCESS BY ROWID” ? I was thinking that if the column is indexed and we select that column then we face a “TABLE ACCESS BY INDEX ROWID” Your thoughts !!

[@Alokkumar-me7pl]

bro, ur voice modulation is similar to Roman Saini (Unacademy cofounder)..🤗 btw nice explanatiom.. can u just make Part2 of it

[@saurabh29101988]

Thanks for the compliment. Will upload soon.

[@ajeetverma1172]

Excellent... Keep it up

[@saurabh29101988]

Thank you.

[@sandhyavijay5621]

what is Hash Join in the given example?

[@piyushnikhade2034]

One question I need to ask that explain plan is used for select clause based queries only ?

[@saurabh29101988]

No we can use it for insert, update and delete also. But not ddl.

[@venkatv2973]

Upload more videos on performance tuning like wait events and different type of locks..

[@kumar-bi1to]

Thank you

[@mohantadibyajyoti]

Please create video on statistics for analyzing issue

[@saurabh29101988]

Sure, will do

[@ziadfawzi]

Thank you.

[@saurabh29101988]

You're welcome!

[@dipakit45]

SIR, GIVE ME INTERVIEW PERSPECTIVE, HOW WILL YOU GIVING ANSWER TO INTERVIEWRS.

[@saurabh29101988]

Looking to create videos on some tricky interview questions.

[@sureshkumar4915]

Super and nice videos