PowerPoint Presentation

[Audio] Good day sir, good day class my name is Nkosi Gibson and today ill be doing a presentation on database indexes..

DATABASE INDEXES. Database.

[Audio] Indexes are used to make queries go faster and they can be found in lots of databases. Indexes make searching go faster so we can use them to speed up our applications or use query times for analytics..

CLUSTERED & NONCLUSTERED. Newspaper.

[Audio] What is the difference between clustered and non-clustered index? First is, a clustered index defines the order in which data is physically stored in a table, an example of this is a dictionary. On the other hand a non-clustered index is stored at on place and the table data is stored in another place, an example of this is a book index..

COST OF INDEX. Money.

[Audio] You might think what a lot of people think when they realize the power of indexes, why not use indexes for everything then all of our queries will be really fast. But there are trade offs, database indexes just like book indexes have cost and there are two cost associated with database indexes. Firstly, additional indexes take up extra space in the database so every index added is additional hard drive space taken up because extra tables are being created, depending on the intended use and the size of the database this can be an issue. Secondly, additional indexes can slow down a database when doing different types of operations, for every index added to a table, updating data or adding additional data is going to be slower because the database not only have to update the original table but the index also.

DBMS. EXAMPLE. Gears with solid fill.

[Audio] MS Access can create indexes automatically, an index is created for any field that you designate as a table primary key. Lets create a primary key on a table, set up the field for the primary key and click on the primary key icon, now click on indexes, you can see the index name primary key is automatically created..