1 00:00:00,310 --> 00:00:03,700 So far we've laid some of the theoretical groundwork for 2 00:00:03,700 --> 00:00:06,180 what's to come in the remainder of this course. 3 00:00:06,180 --> 00:00:08,060 Let's review a little before moving on. 4 00:00:09,160 --> 00:00:13,060 We learnt that relational databases are how we organize data 5 00:00:13,060 --> 00:00:14,575 in a structured manner. 6 00:00:14,575 --> 00:00:19,100 Structuring data in a well thought out manner reduces disk space, 7 00:00:19,100 --> 00:00:24,055 eliminates redundant data, removes the possibility of updates anomalies, and 8 00:00:24,055 --> 00:00:26,590 boosts query performance. 9 00:00:26,590 --> 00:00:28,495 We learnt about normalization. 10 00:00:28,495 --> 00:00:33,863 This is the process of identifying and eliminating things in our database design, 11 00:00:33,863 --> 00:00:39,130 that would make our database perform poorly or have inconsistent data. 12 00:00:39,130 --> 00:00:41,520 Last, we learnt about sets. 13 00:00:41,520 --> 00:00:44,460 And how that applies to relational data. 14 00:00:44,460 --> 00:00:50,420 We saw how intersect union and except might look in a very simple example. 15 00:00:50,420 --> 00:00:53,580 I have a quick assessment for you to get you ready for the next stage.