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Showing posts from May, 2018

DAT 601 - Robin Le Couteur - Class reflection - 1/06/2018

Friday, June 1, 2018 Class Reflection In this class we started off looking at what we need to include in milestone 3 We need to include all the work we did in the two other milestones, and we need to follow a number of steps to implement our physical design. I also learned a new word in this class. This word is 'cogitate' defined as the following: "cogitate ˈkɒdʒɪteɪt/ verb formal think deeply about something; meditate or reflect. "he stroked his beard and retired to cogitate" synonyms: think (about),  contemplate ,  consider , give thought to, give consideration to, mull over, meditate (on), muse (on), ponder (on/over), reflect (on), deliberate (about/on), ruminate (about/on/over), dwell on, brood (on/over), agonize (over), worry (about), chew over, puzzle (over), speculate about, weigh up,  revolve , turn over in one's mind,  review ,...

DAT 601 - Robin Le Couteur - Class reflection - 18/05/2018

Friday, May 18, 2018 Class Reflection In this class Todd quickly showed us how to install the AdventureWorks database. It involved downloading the backup file and restoring it. That was pretty easy so I got that installed before we moved on. We then looked at subqueries . There was a huge number of examples we went through that show how you can use subqueries.

DAT 601 - Robin Le Couteur - Class reflection - 11/05/2018

Friday, May 11, 2018 Class Reflection In this class we covered some useful SQL queries. GROUP BY The first statement we covered was the GROUP BY statement. This statement groups results under the specified columns like this: SELECT Country, Region, SUM(Sales) As TotalSales FROM Sales GROUP BY Country, Region; This statement will group the sum of sales per region, and each region will be grouped under the country it belongs to. There is also GROUP BY ROLLUP and GROUP BY CUBE statements which group them differently. You can also group GROUP BY statements together with a GROUPING SET statement. It is a simplified version of a UNION that concatenates GROUP BY statements into one table of results. VIEW A view is a useful for giving certain users a certain view of the database. In a view you can set the tables and columns that are able to be seen in that view, then if someone uses that view they can only access the data available in the view. It...