These are the topics for week 2:
- Identifiers (Primary key, Foreign key, Composite key)
- Relationships (One-to-One, One-to-Many, Many-to-Many)
- SQL clauses
- Joins
- Aggregate functions
- Distinct
- Group By
- Having
- Indexes
- Domain modeling
This week, we dive deeper into SQL and how to structure your tables. Let's start by looking into identifiers that allow you to add constraints to your database here. After that, let's look into relationships between tables. There are three types of relationships (one-to-one, one-to-many and many-to-many), read about when to use them over here.
Next, we will look at more complex SQL commands that are needed now that the table structures are getting more complicated. Let's look into the advanced SQL commands and when to use them here.
With more complex and bigger databases, performance can become a problem. To help you solve this, you can configure your database in such a way to speed up specific queries using Indexes. Finally, with all of these relationships between multiple tables, it can become a little hard to keep track. To help visualise your databases, we generally use what is called an Entity Relationship Diagram, read all about them here.
Bonus: We have a bonus video here of one of our mentors (@Unmesh on Slack! Thank him if you found it useful) going through a practical example of how to deal with the asynchronicity of working with databases.
Bonus 2: A second bonus video here that goes through some of the topics of this week: keys, relationships and joins. Again it is @Unmesh on Slack, a thanks if this helped you is much appreciated!
If you haven't finished all the material yet, then continue with it this week.
Have you gone through all of the materials? High five! If you feel ready to get practical, click here.