Wed, 28 May 2014
There are three categories of joins that you can make use of in SQL:
But before we dive into the categories of joins, we first need to have an understanding of what a join really is.
Joins are used in SQL to bring together all the relevant data from multiple database tables. Remember that we've broken data down into multiple tables and established relationships between the tables.
... More via show notes: http://howtoprogramwithjava.com/session46
Fri, 23 May 2014
In this SQL tutorial episode/post we’re going to learn how to enforce our SQL relationships that we’ve already learned about. We’re going to be tackling the one-to-one and many-to-many relationships and we’re going to learn how to write the code to enforce these relationships in our database.
As outlined in the podcast, we are going to be focusing on the many-to-many relationship with the
Show notes available via http://howtoprogramwithjava.com/session45
Wed, 14 May 2014
You’ve learned all about how to create sql queries to read, write, update and delete data… but you haven’t yet learned how to create the tables where you’ll be doing the reading, writing, updating and deleting.
So that’s what today’s podcast is all about, be sure to click the play button above this to listen to the show and then follow along with the notes via http://howtoprogramwithjava.com/session44
Tue, 13 May 2014
Show Notes available via: http://howtoprogramwithjava.com/session43
In this post we will be expanding on the topic of database relationships and touch on two that are less common but just as useful.
The many-to-many database relationship is used when you are in the situation where the rows in the first table can map to multiple rows in the second table… and those rows in the second table can also map to multiple (different) rows in the first table.
A One-to-One relationship means that you have two tables that have a relationship, but that relationship only exists in such a way that any given row from Table A can have at most one matching row in Table B.