The document provides an overview of SQL and relational databases: - SQL is a widely used language for database administration, enterprise applications, and data-driven websites. It allows querying and managing data stored in relational databases. - Relational databases are based on Codd's relational model and store data in tables made up of rows and columns. They support constraints, relationships, and other features to ensure data integrity. - Common SQL statements include DDL for defining database schema, DML for manipulating data, and DCL for controlling access. Key DML commands are SELECT, INSERT, UPDATE, DELETE. SELECT can include WHERE clauses with operators like LIKE, IN, BETWEEN to filter results.

1. SQL200 Based on SQL Clearly Explained by Jan Harrington SQL Programming Module 1 – Relational Database Background, Basic Single Table Retrieval Operations

2. SQL200 P.O. Box 6142 Laguna Niguel, CA 92607 949-489-1472 http://www.d2associates.com [email_address]

3. SQL Programming Course focus is SQL language Widely used for: Database administration Enterprise application development Data driven web sites A foundation skill for eBusiness and almost all major business applications that use relational databases

4. SQL Programming A basic knowledge of query systems, perhaps via MS Access, or some programming knowledge, is desirable We will use GUI tools or Access “SQL View” almost exclusively

5. Relational Database Evolution Based on Codd’s paper Early commercial efforts focused on Unix First mainframe implementation by IBM - precursor to today’s DB2 First PC implementation in early 80’s by Oracle

6. Relational Database Basics Storage Databases Tables Rows Columns Indexes Views Cursors Application interfaces

7. Relational Database Table

8. Constraints Database Domain Uniqueness Relationship Cardinality 1 to 1 1 to N Other Business Rule Triggers Stored Procedures

9. Relational Database with constraints

10. Database Management Systems Positioning Chart VLDB Enterprise Workgroup Single user Spreadsheet # Users Cost

11. System Architecture Access MDB File Server Architecture Access

12. System Architecture Oracle DB Visual Basic App Client/Server Architecture Access  SQL 

13. System Architecture Oracle DB Browser Web Architecture Web Server  SQL 

14. Approaching SQL Relatively simple Two main environments Interactive (This course) Embedded Static (Compiled) Dynamic

15. SQL Standardization ANSI standardization First standard in 1986 SQL 89 SQL 92 SQL 99 Various vendor extensions Microsoft/Sybase: T-SQL Oracle: PL/SQL

16. SQL Conformance Entry Intermediate Advanced Most are at least entry level

17. SQL Statements Data Manipulation Language (DML) Data Control Language (DCL) Data Definition Language (DDL) Note: SQL 99 changes these to seven types

18. SQL DDL Data definition language (DDL) Create, alter, drop, etc. Frequently implemented via various CASE tools: Visio, Embarcadero, ERWin, etc. But very useful for database administration

19. SQL DCL Data Control Language (DDL) Grant Revoke Constraints

20. SQL DML Data Manipulation Language (DML) Select Insert Update Delete

21. SQL Statement Processing Parse Validate Optimize Access Plan Execute

22. Bookstore Sample Database Before we continue (note: instructor may have already done this)… Load the sample database if you haven’t already Use Access import table feature, or Run SQL script, or Use Access upsizing wizard

23. Text Conventions In Access character strings are normally surrounded by double quotes “ Jones” In an enterprise database such as Oracle or SQL Sever, then single quotes ‘ Jones’ Be sensitive to the environment of your class in copying scripts from the PowerPoint slides!

24. Date Conventions In Access date are normally surrounded by pound signs #12/23/2004# In an enterprise database such as Oracle or SQL Sever, then single quotes ‘ 2004-12-23’ MySQL ’ 12-23-2004’ SQL Server ’ 23-DEC-04’ Oracle Be sensitive to the environment of your class in copying scripts from the PowerPoint slides!

25. SELECT Basic Syntax ( Projection ): Select <column-list> or <*> From <table-list>

26. SELECT Basic Example ( Projection ): select customer_last_name, customer_street from customers

27. MS Access SQL Query

29. SQL Server Query

30. SELECT with Where Clause Example ( Restriction plus Projection ): Select <column-list> From <table-list> Where <selection-criteria>;

31. SELECT with Where Basic Example ( Restriction plus Projection ): select customer_last_name, customer_street from customers where customer_last_name = “Jones”

32. Select with Where

33. On Your Own Find books written by Mark Twain Show title, publisher, year

34. Complex Predicates Follow normal boolean logic Select customer_last_name, customer_street From customers Where (customer_last_name = ‘Jones’ or customer_last_name = ‘Smith’)and customer_state=‘NY’

35. Select with Complex Where

36. Complex Where Result

37. Special Operators Can be used in where clause LIKE IN BETWEEN IS NULL

38. Like (“Wild Card Matches”) ANSI Where customer_last_name like “Jo%” Like “Jo_” Access Where customer_last_name like “Jo*” Like “Jo?”

39. IN Select * From customers Where customer_last_name in (“Rizzo”, “Jones”, “Garcia”) The list in parentheses can be replaced by a subquery. We will study this later.

40. SQL Where Clause with IN

41. IS NULL Select * From customers Where customer_street IS NULL SQL uses three valued logic. Must use IS NULL to test for unknowns. A null is NOT the same as blank or empty.

42. On Your Own Find all customers with an address not equal to 4592 Maple Lane Was Peter Johnson selected? Why or why not?

43. BETWEEN Select * From orders Where order_date BETWEEN #1/1/99# and #12/31/99# Note: date formats vary from product to product. Above is Access syntax, SQL Server uses single quotes. Ex: ‘1/1/99’

44. Where with Between

45. Removing Duplicates Select DISTINCT customer_city From customers List once each city in which there are customers Removes duplicate rows from result set

46. Removing Duplicates

47. Sorting – ORDER BY DESC will sort in descending order Basic syntax : Select <column list> From <table list> Where <selection criteria> Order by <column list> [DESC]

48. Sorting – ORDER BY Select * From customers Order by customer_state, customer_city Example: List all records sorted by state, city

49. Sorting Results with Order By

50. Selecting Top Records Select Top 5 (or top 25 percent) Customer_last_name , contact_zip From customers Order by customer_zip desc ; List largest 5 zips or top 25 % of them…

51. SQL Exercises List all books whose publisher name begins with “H” or “T”; sort by title [hint: use LIKE] List all customers whose last name ends with “S”; sort by state, city, last name Find the order numbers of orders with order dates in 1999; sort by order #. [Hint: use BETWEEN] Find the order numbers and order dates of all orders with a “2” in column 2 of the credit card #; sort by order date descending [end module]