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SELECT * FROM....Writing SQL Queries...

This week is my fourth week on the spin being involved in a Learning Tree Course. This week we have double bubble. I teaching a Course today and I'm Producing a course tomorrow.
Today I will be teaching a one day course titled Writing SQL Queries. This course provides and introduction to writing queries, using the SELECT statement in SQL.

If you would like to join Learning Tree I have some great courses available at a Great price. Check out the Great Value IT Training page for this week's offers.

I'll be live blogging today's  one day virtual event.

16:25 That's a wrap - a very good, the attendees seemed to enjoy the course. They're all off to practice their new skills in the sandbox environment and I'm off too...For the producer meeting for tomorrow's 244 event. I'll see you then.

16:05 Last exercise of the day looking at SET operators

15:50 SET Operators UNION, UNION ALL, INERSECT, EXCEPT to finish the day.

15:30 Exercise on Outer Joins

15:10 Started looking at out joins, I want all the rows from t1, regardless of there being a match in t2

SELECT T1.c1, T2.c1
FROM T1
LEFT OUTER JOIN T2
ON T1.C2 = T2.C2

14:52 Exercise on Inner Joins

SELECT T1.c1, T2.c1
FROM T1
JOIN T2
ON T1.C2 = T2.C2

14:38 Interesting discussion around inner joins and why table aliases are important. Including making your code easier to read


14:00 Chapter 3 Joins. Things are getting interesting

13:40 First lab after lunch and we're handling NULL values

SELECT C1
,C2
COALESCE (C3,0)
C2 +  COALESCE (C3,0) AS TotalPay
FROM T1

13:10 Started backed after lunch with a discussion around NULL values and how to handle them in SQL queries.

12:10 Exercise done and we're off to lunch. Well I am, This is a virtual event, so everyone is attending online today. The classroom is empty.



11:48 Just starting exercise 2.2 Writing queries with restrictions. That is WHERE clauses. Also looking at sorting results with ORDER BY

SELECT C1,C2,C3
FROM T1
WHERE C1 = 'X'
ORDER BY C2 Desc

11:05 First exercise in chapter 2 and we're writing single table selects

SELECT C1,C2,C3
FROM T1

10:20 Its the first coffee break of the morning. Exercise 1.1 completed.

10:10 With the introductions complete and the introduction to the class environment, a little refresher on relational database theory the class are looking to complete the first lab.

09:00 We are just about to start...We will be covering

SELECT
FROM
WHERE
GROUP BY
HAVING
ORDER BY

With some joins thrown in for good measure. It should be a fun day.

08:30 The class is setup and we're good to go. This is a virtual event so we have nobody in the class. everyone is attending online.


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