This document outlines the course expectations for a SQL lecture series, covering topics such as SQL basics, data manipulation, and database management. It mentions the importance of understanding various database structures, commands, and SQL functions in practical applications. The lecture series will progressively address advanced concepts including relational databases, data types, and SQL functions like window functions and date operations.

1. Standard Query Language
SQL
Lecture 1

2. Course Expectations
◈ What do you expect from this course?
◈ Prior Exposure to SQL?
◈ My Experience with SQL.

3. Course Expectations
SQL
• Loading data
• Writing queries
• Knowing the
terminology
Excel
• Becoming
proficient with
formulas and
spreadsheet
structuring
• Learning other
useful features
PowerBI
• Understand what
makes a good
visualization
• Learn how to tell
a story
• Link dashboards
to live data

5. Database
◈ USER DBMS DATABASE

6. SQL and Databases
◈ SQL is the language for generating, manipulating, and retrieving data
from a relational database.
◈ Types?

7. ◈ Table, Tuples, Fields, Schema, Primary Key, Foreign Key
◈ Why not Excel?
◈ SQL (Sequel) Vs. MySQL

8. Relational Databases

9. SQL Statements

10. Creating Table and Databases

11. Data Types

13. Material to Cover
◈ Databases (Their control and administration)
◈ Select statement
◈ Selection of Database from toolbar or with command
◈ HR Data exploration: How do we start
◈ Entity Relationship Diagram (ERD)
◈ Relationship type: Many, One
◈ Joining Criteria
◈ Importing the HR tables: Countries and Customers
◈ Use of underscore instead of space

14. One to One: You and your ERP
Many to One: You all studying from me
One to Many: Me teaching you all
Many to Many: Other students studying from
same professor that you have studied from.
Relationship of Customers to Country?

17. Standard Query Language
SQL
Lecture 3

21. ERD Diagram
◈ A customer complains about an employee, how to find the data of the
employee?
◈ Why not Country Name as PK and why Country ID?

22. Star Schema

23. Snowflake Schema

24. Topics to Cover in Lecture 2
◈ Text vs Numbers
◈ Comments in SQL: #, --, /*
◈ Not equal to sign
◈ Between command
◈ '[acs]%’ '[!acs]%’
◈ '[a-f]%

25. Topics to Cover in Lecture 3
◈ Importing Date columns as text
◈ Color coding of SQL: Gray = Operator, Pink = Function
◈ YEAR, MONTH
◈ Temporary Table: INTO #hktemp, INTO ##hktemp
◈ Copying the data to Excel

26. Topics to Cover in Lecture 4
◈ Refresher of Group By Function
◈ Distinct feature in Excel – Not Done
◈ Flow of Processing SQL commands
◈ ‘Having’ does not depend on Select statement
◈ Distinct feature in Excel
◈ Count Distinct *

27. Topics to Cover in Lecture 5
◈ ORDER BY 2 or more columns
◈ ORDER BY on String

28. Inner Join

29. Left Join

30. Right Join

31. Full Outer Join

34. Null/Not Null

35. Null/Not Null
◈ Select * from customer where city is NULL;
◈ Is not same as
◈ Select * from customer where city = ‘NULL’;
◈ lets say id <> 2, then it won’t pull up the records with id = null. You have to specifically build that into
condition that id <> 2 and id is null.

36. SQL Functions
◈ MODULUS or %: Checking the Remainder:
◈ select distinct city from station where ID%2 = 0;
◈ For Even: Either do MOD(ID, 2) = 0 or ID%2 = 0.
◈ For Odd: Either do MOD(ID, 2) = 0 or ID%2 = 1.
◈ POWER(X, 2): To raise x to the power (exponent) of 2.

37. SQL Functions

38. SQL Functions
◈ TRIM([characters FROM ]string): removes leading spaces or the characters you specify. LTRIM, RTRIM.
◈ Window Functions:
◈ Over() to open a window: If no column is passed to over(), it is going create one window for all the
records, will iterate over all rows.
◈ Select *, max(salaray) over() as max_salary from employee: this will show max salary among all the
employees.

39. SQL Functions
◈ ROW_NUMBER() to apply row numbers in a table. Specification in the Over() clause will tell us how to
apply the row number.
◈ Example:
◈ Select a.CITY, a.CITY_LENGTH FROM
◈ (SELECT CITY, LENGTH(CITY) AS CITY_LENGTH,
◈ Row_number() over(order by LENGTH(CITY) asc, city asc) as short_length_rn,
◈ Row_number() over(order by LENGTH(CITY) desc, city asc) as long_length_rn
◈ FROM STATION) as a
◈ where a.short_length_rn = 1 or a.long_length_rn = 1
◈ order by 1 asc;

40. SQL Functions
◈ DateAdd
◈ Datediff
◈ Left
◈ Right
◈ GetDate