Learn how subselects are a convenient way of making your data available in different forms, while keeping the your database schema simple and well organized.
- [Narrator] A subselect is, effectively, nested queries.…In SQL, the result of a select statement…is, effectively, a table and can always be used…as you would use a table.…Because of this, a select statement…may be used as a data source in another select statement.…This usage is called a subselect.…We'll select the world database for this example…and I'm gonna come out here to our…exercise files for chapter 11…and I'm just going to grab those statements there…from the create table to the select from T…and I'll paste that in here and run it.…
And, you see we've created a table with two columns…and we're inserting in these values.…And when we look at these values,…we'll notice the first two characters is a two-letter code.…In column A, that two-letter code is a state code…and in column B, that two letter code is a country code,…a standardized country code.…And, then there's these other numbers,…which we're calling it a code for our purposes,…because this is an interesting way to pack data…and you'll find packed data like this a lot of databases.…
- Understanding SQL terminology and syntax
- Creating new tables
- Inserting and updating data
- Writing basic SQL queries
- Sorting and filtering
- Accessing related tables with JOIN
- Working with strings
- Understanding numeric types
- Using aggregate functions and transactions
- Automating data with triggers
- Creating views
- Defining functions in PHP
Skill Level Beginner
2. SQL Overview
3. Fundamental Concepts
7. Dates and Times
Dates and times1m 52s
11. Views and Subselects
12. Defined Functions
13. A Simple CRUD Application
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