1. LSP 121 Week 1 Intro to Databases

2. Welcome to LSP 121 Quantitative Reasoning and Technological Literacy II Continuation of quantitative data concepts from LSP 120 We will spend three weeks storing and retrieving data using a database Given a data set, what is its mean, median, standard deviation and more (descriptive statistics)? Given two sets of data, is there a correlation?

3. Welcome to LSP 121 Continuation of quantitative reasoning concepts from LSP 120 Given a set of data, can we calculate probability and risk? How do we manipulate data, compress it, or check for errors - algorithms If you feel you know this material, take the test Let’s get started!

4. Are Databases Important? Virtually every major area of study in college and in the real world needs to store and retrieve data Commerce (sales, marketing, production, management, …) Education (daily operations, research, …) Healthcare Government Do you really want to enter the workforce and not know what a database is and how they are created?

5. Why a Database (and not a spreadsheet)? You have too many separate files or too much data in a single file You need to look at the data in many different ways You need to share the data You want to secure access to the data and control data values

6. Basic Terms Table – an object you define and use to store data. Each table contains information about a particular subject, such as customers, patients, or orders Fields – tables contain fields (columns) such as first name, street address, score Record – a logical collection of fields Query – an object that provides a custom view of data from one or more tables

7. Field Attributes (Data Types)  You want to create fields for Name, Address, Telephone, Amount Paid,…  Text – the most common!  Number – do NOT use unless you plan to do arithmetic with this field  Date/Time  Currency – use with money fields  AutoNumber – similar to Number but Access automatically inserts the numbers for you  Yes/No (and others)

8. What is a Primary Key?  Most tables should have a primary key, but it is optional  A primary key is a field that can uniquely identify every record  For example, your student ID is a primary key in a lot of databases here at DePaul (every student ID is unique – no duplicates)  Social Security number primary key for a lot of government databases  If you are searching for a particular record, you can use the primary key

9. What is an Index? You can make any field an index An index also let’s you search for one or more records An index can require unique values (like the primary key) but an index can also allow duplicate values You can search a database on any field, but the search will be faster if you make the field an index

10. Table Example Let’s create a table for the following: Home address / phone book * What is the primary key? * What are the indexes?

11. Let’s Practice Let’s run the program Access and create a simple table and then enter some data for the example Home Address Phone Book (Smith, Jones, Anderson, Abbott) (in Oak Park, Chicago) Did you correctly assign the type for each field? Did you select the field as an index? Did you create a primary key?

12. Queries Let try a couple queries Don’t use the Query Wizard – we’ll design our own queries What is Smith’s phone number? Show all people living in Oak Park ??? STOP. Let’s do Activity 1.

13. Importing Data into a “Flat” Access Database Many times you want to take an existing data set and “import” it into an Access database The existing data set can be plain text (.txt), a spreadsheet (.xls), or other forms of existing databases Let’s consider the example of importing a spreadsheet into an Access database

14. Importing Spreadsheet Data Create a new (blank) database (unless you are importing into an existing database, then simply open that one) Select External Data from the top tabs Select the appropriate type of file that you want to import

15. Importing Spreadsheet Data You probably want to import the data into a new table If the spreadsheet you are importing has more than one worksheet, select the appropriate worksheet Does the first row contain column headings?

16. Importing Spreadsheet Data Now you can tell the wizard which fields should be indexed in the new table Choose your own primary key or let Access add a primary key? Give the table a name and click on Finish You may have import errors – check the file xx$_ImportErrors

17. Importing Spreadsheet Data Let’s try an example – we will import the data in spreadsheet Presidents.xls Open the QRC website and copy the file Presidents.xls to either My Documents or the Desktop (may not be able to copy to Desktop) Run Access and perform the import operation on the Master worksheet Try a FIND or two Try a FILTER or two

18. Finding a Record A very simple way to look for a record But you can only search in one table, and you can only look for one field Open the table, then on the Home tab click on Find (or CTRL-F) Enter values as necessary Wildcard character: * Find is nowhere near as powerful as performing a query (later) We’ll try FINDing a record in a few moments

19. Filtering Records If you want to see all the rows in a table that match any part of a value, you can use the Filter command A couple different forms of Filter. Let’s look at Filter by Selection Open the table you want to filter. Highlight the field you want to filter on. Then on the Home tab click on Selection To undo filtering, click on Toggle Filter We’ll try filtering in a few moments

20. Further Questions How does Google work? Should Google restrict its searching capabilities to comply with a government? What is data mining? STOP. Now do Activity 2.