Love these easy-to-digest videos to cover missing pieces of knowledge or act as refreshers! Also, the teaching style. Thank you!
@DatabaseStar Жыл бұрын
Glad you like the video!
@henriquelisboa33817 ай бұрын
Thank you very much! I'm a newbie with databases but I need to work with one for a project and this video has the perfect balance between easy to understand and digging into advanced concepts! Wish you the best!
@DatabaseStar7 ай бұрын
Thanks, glad it was helpful!
@tomservo75 Жыл бұрын
This is really nice, would you ever consider making a more advanced version, for people who know what indexes are but need advice on where to create them, what columns to add, single vs. multi-column
@DatabaseStar Жыл бұрын
Great idea! I can create a video on that.
@ItsWithinYou Жыл бұрын
Super! Many thanks for sharing!
@DatabaseStar Жыл бұрын
No problem, glad it helped!
@rafaelbraga3d2 жыл бұрын
Thanks for the explanation. It was very very helpful. Now I really understand well indexes.
@DatabaseStar2 жыл бұрын
Glad it was helpful!
@Felipe_Matheus_1991Ай бұрын
Thanks your video help me very much! Success to you my friend!
@DatabaseStarАй бұрын
Glad it was helpful!
@WaliSayed8 ай бұрын
very useful, thank you!
@DatabaseStar8 ай бұрын
You’re welcome!
@arunajay8497 Жыл бұрын
great intro video, thank you
@DatabaseStar Жыл бұрын
Thanks!
@nicholassmith6412 Жыл бұрын
another helpful video, thanks again
@DatabaseStar Жыл бұрын
Happy to help!
@weekendprogrammer75459 ай бұрын
Thank you for this video, very helpful and explained so that any one can understand. I know it's a bit more to ask, but if it's possible to actually see the reduction in the time taken by actually running the queries in some database would be great.
@DatabaseStar9 ай бұрын
You're welcome! That's a good idea, I do have some other videos on my channel that show the query before and after.
@weekendprogrammer75459 ай бұрын
I'll have a look at your videos list.. Thank you, really Appreciate the reply @@DatabaseStar
@omega.developer2 жыл бұрын
very nice explaination
@DatabaseStar2 жыл бұрын
Thanks!
@krs-tube7 ай бұрын
Thanks for the intro vid. You mentioned you're going to explain when to use clustered vs non-clustered index, but you didn't do it. Could you share your thoughts.
@DatabaseStar7 ай бұрын
Great point! I’ll create a video on this in the future
@siddharthapenchala81462 жыл бұрын
Thanks for the brief Explanation, Sir. Can you please clarify my doubt. Sir, I have created an index but the optimizer is not using it? What are Such cases where optimizer doesn't use the index?
@DatabaseStar2 жыл бұрын
It depends on the database, but generally it's because the database has found a better way. It could be the columns in the index do not match the query. It could be the distribution of the data means the index won't help/
@8485Rockstar Жыл бұрын
Great.......I have one question I don't know is it valid or not. Suppose I created one index on the primary key of one table, Will it run automatically, or need to create any job for that?
@DatabaseStar Жыл бұрын
Good question. Yes it will run automatically when needed, there's no need to create anything else to get it working.
@datalore6187 Жыл бұрын
Does order matter when choosing which columns in the WHERE clause? Say for example I have a primary key index of (ID, LOCATION). There will be many ID's in the table, but only 5 LOCATION values. In my SELECT statement, should I use "SELECT * FROM EMPLOYEES WHERE ID = :P_ID_PARM AND LOCATION = :P_LOCATION_PARM" or should I use "SELECT * FROM EMPLOYEES WHERE LOCATION = :P_LOCATION_PARM AND ID = :P_ID_PARM"? Does it matter? Thanks!
@DatabaseStar Жыл бұрын
Good question! No, I don't think the order of the WHERE clause matters (at least I haven't seen or read anything about this being considered by the database). The order of columns when creating an index with multiple columns definitely matters, but in your example I think both queries would be the same. You could check the execution plan for both queries and see what the differences are
@datalore6187 Жыл бұрын
@@DatabaseStar Thank you! Interestingly enough, I ran a query both ways. It turns out that SELECTing on the column with the most values first speeds things up. So in my example, if I first SELECT on the ID column, and then SELECT on the LOCATION column, the results are faster than if I first SELECT on the LOCATION column, and then the ID column. Just wanted to share.
@RoysIdea8 ай бұрын
B-tree seems very complicated. Or is this caused by the example image?
@DatabaseStar8 ай бұрын
It could just be the example image. I include it to explain how it works, but for most of the time we don't really need to know how it works.
@Kleberei3 ай бұрын
@@DatabaseStar Because that example image does not visually represent a B-Tree. Every node, except for the root and the leaves, has at least ⌈m/2⌉ children and values do not repeat in a B-tree.