M I C R O S O F T A C C E S S : P A R T 2 G E T T I N G I N F O R M A T I O N O U T O F Y O U R D A T A

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1 M I C R O S O F T A C C E S S : P A R T 2 G E T T I N G I N F O R M A T I O N O U T O F Y O U R D A T A Michael J. Walk ALC Instructor michael@jwalkonline.org SUMMARY Now take your access database and turn it into an information machine! Learn how to take hundreds of thousands of pieces of information from multiple tables and extract, organize, summarize, and analyze only the information you want. Then learn how to put that information on a visually appealing report. Prerequisites: all topics covered in Part 1, including: 1. What an Access database is and how it is different from Excel. 2. The purpose of and creation process for basic tables, queries, forms, and reports. 3. Basic knowledge of different data types. 4. How to create dropdown and check boxes in your tables. 5. How to switch between object views (e.g., for forms: design view, form view, and layout view).

2 TABLE OF CONTENTS Summary... 1 How to Use This Handout... 3 Click Paths... 3 Keyboard Directions... 3 DAtabase Relationships... 4 Creating Relationships in Access... 5 Importing Data General Instructions... 7 Field Data Types to enforce during import of Class Data... 7 Importing Quirks... 8 Advanced Query Design... 9 SELECT QUERIES Exploring Criteria... 9 SORTING RESULTS... 9 AND VS. or Criteria Syntax Using Relationships in Queries Special Select Queries Calculating Totals in Queries Retrieving a certain number of records Prompt your User for a Criteria Value ACTION QUERIES alter or manipulate the data in your tables(s)... 16

3 HOW TO USE THIS HANDOUT This handout serves as a point of reference for your workshop. However, you may also use the handout after the class is over to help you remember how to perform some of the tasks covered during the workshop. CLICK PATHS Throughout this handout, you will be given directions to perform a series of mouse clicks also called a click path. For instance, to save a change to an Access object, you should click on the File tab in the ribbon, then click on Save. In this handout, that click path is displayed using a bold font for the words to click on connected by a single right-pointing arrow ( ): File Save In some cases, you must find the correct section of the ribbon before clicking on an icon or button. In these cases, the ribbon section will be highlighted in gray, for example: External Data Import & Link Excel In this example, Import & Link is a ribbon section. KEYBOARD DIRECTIONS You also will be given directions to press certain keys on your keyboard. There are two kinds of key press sequences: (1) simultaneous and (2) sequential. 1) Simultaneous key presses refers to keys you have to hold down together to perform a task. Simultaneous key presses are displayed using the plus sign (+) between the keys to be pressed typed in caps. For example, the find box is opened by pressing CTRL + F. CTRL stands for the control key. ALT stands for the alternate key. WIN stands for the windows key (only applies to PCs with windows keys). 2) Sequential key presses refers to keys you have to press in sequence (one after the other it is not necessary to hold them down). Sequential key presses are displayed using a pipe character ( ) between the keys to be pressed typed in caps. For example, one way to save your file under a new file name is to type ALT, then F, then A. This would be displayed as: ALT F A. If you like keyboard shortcuts, Microsoft Office has provided a very robust listing of them at: (Or simply search access keyboard shortcuts.) I provide a lot in this workshop, but online lists are exhaustive.

4 DATABASE RELATIONSHIPS To get the full power and advantage of having your tables in Access, you ll need to design and specify relationships between your tables. A relationship exists between two tables when they share a field that contains the same element of data. A simple example of 5 tables and 4 relationships. Reference Tables Transactional Tables Customers CustID (primary key) FirstName LastName CustDate Employees EmpID(primary key) FirstName LastName HireDate Products ProdID (primary key) Description Cost RetailPrice QtyOnHand Orders OrderID (primary key) Date CustID Total PayMethod EmpID OrderDetails DetailID (primary key) OrderID ProdID TimeStamp Qty UnitPrice Examples of Each Table: (relationships are color-coded) Customers CustID FirstName LastName CustDate 1 Vanessa Hudgens vhudgy@ .com N 2 John Bunyan jbunny@ .com Y Products ProdID Description Cost RetailPrice QtyOnHand MLK001 Milk, gallon $2.99 $ BEF001 Steak, 1lb $2.53 $ TP002 Toilet paper, soft $3.43 $ Orders OrderID Date CustID Total PayMethod EmpID /17/ $ Cash /17/ $3.99 DSCVR 002 OrderDetails DetailID OrderID ProdID TimeStamp Qty UnitPrice MLK001 3:54:55 PM 1 $ BEF001 3:55:23 PM 20 $ MLK001 3:56:17 PM 1 $3.99 Employees EmpID FirstName LastName HireDate 1 Vanessa Hudgens 12/16/ John Bunyan 12/16/2007

5 These relationships serve two very important purposes: 1) They allow you to store repetitive information with very little pieces of data. For example, I know WHO bought WHAT without needing to constantly store the customer name and product description every time. I only need to store the CustID and the ProdID. 2) They allow you to perform complex queries to efficiently extract related data from multiple tables. For example, what are the addresses of customers who bought milk on 12/17/2007? These data are stored in 4 different tables: Customers, Orders, OrderDetails, and Products; however, the relationships will allow you to query your data and view it easily. CREATING RELATIONSHIPS IN ACCESS To begin, you ll have to import data from the class website; follow the instructions on Importing Data (p. 7) and then come back to this page. Note: Related fields MUST BE THE SAME DATA TYPE. Integers can only relate to integers. Text can only relate to text, etc. 1) Have all necessary tables (with their fields properly specified / designed) in your database. (You can add tables later and create additional relationships, but you ll need the tables in the database before you can relate them.) 2) Open Database Tools Relationships Relationships 3) This will open the Relationships Window and the Show Table box will pop up. Select all tables you want to work with that have relationships. Add the tables to the Relationships Window by double clicking on each, or selecting each and clicking on Add. Then click Close. 4) Your selected tables (field lists) will be added to the Relationships Window. I recommend expanding the size of the tables so you can see all fields.

6 5) To create the relationships between tables, simply perform a drag-and-drop maneuver with your mouse from one field name to the related field name. Two relationships exist in these tables: a. BusRoutes.RouteNumber Surveys.BusRoute i. Click on the RouteNumber field in the BusRoutes table, ii. Drag to the BusRoute field in the Surveys table and drop iii. Click Create b. Riders.RiderID Surveys.RiderID i. Click on the RiderID field in the Riders table, ii. Drage to the RiderID field in the Surveys table. iii. Click Create 6) When you re done, your Relationships Window should look like this. Then click Close in the ribbon.

7 IMPORTING DATA GENERAL INSTRUCTIONS 1. External Data Import & Link 2. Choose file type: a. Access, Excel, Sharepont, Text, XML, and much, much more 3. For Excel Importing: a. Locate data source (using Browse) b. Choose to import table (or to link 1 table), click Next c. Indicate whether the first row contains column headings or not, click Next d. Place cursor in first column, edit properties if needed, then proceed to remaining columns. When done, click Next. i. Name ii. Data Type (Access will attempt to interpret the data automatically, but you may have to change these data types see data types in the Access Part I handout) iii. Indexed (speeds up searching if you typically use a particular field for searching) 1. No: not indexed 2. Yes (Duplicates Ok): Indexes the field, allows duplicates in the field 3. Yes (No Duplicates): Indexes the field, does not allow duplicates *like a Primary Key* e. Choose whether to add primary key, select primary, or have no primary key. Click Next f. Type a name for the table (should be self-explanatory), click Finish g. You should receive a message telling you whether or not the import process was successful. h. Choose whether or not you would like to save the import steps for a later time (recommended if you ll be doing the import more than once). You can even create an Outlook event that will remind you to perform the import. FIELD DATA TYPES TO ENFORCE DURING IMPORT OF CLASS DATA Surveys worksheet from RateYourRideData 1) SurveyID should be a LONG INTEGER and should be your PRIMARY KEY 2) RiderID should be a LONG INTEGER 3) BusRoute should be an INTEGER 4) Rating should be an INTEGER 5) Complete should be YES/NO Riders worksheet from RateYourRideData 1) RiderID should be a LONG INTEGER and should be your PRIMARY KEY 2) Subscribed should be YES/NO BusRoutes worksheet 1 A linked table maintains a link (or connection) to the original file, but does not actually hold any of the data in your database. When you change the contents of the Excel spreadsheet, the linked table in your database will also change automatically.

8 1) RouteNumber should be INTEGER and should be your PRIMARY KEY IMPORTING QUIRKS Sometimes when you import from Excel, weird things happen. This can be causes by rouge data, blank rows, or corruption in the source file. There s a good article on these issues: Also, here s a few that you ll have to deal with in class. 1) Yes/No data-type fields a. Access cannot import data as a Yes/No field if Excel has text in the column. For example, the words Yes and No in your Excel file will not convert into the Yes/No data type in Access. b. Your Excel data must either be 1s and 0s (1 for true) or the Excel equivalent of TRUE or FALSE. You can get this Excel equivalent by simply typing the word TRUE or FALSE in the Excel cell. c. When imported, the data in your Access table with either display as numbers or as Yes/No. If you want the checkboxes to appear, you will have to change the Display Control of the field using the following steps: i. Open your table in design view (Home Views Design View or Right-Click on the table name in the navigation pane and select Design View) ii. Find the YES/NO field and click in the field row. iii. In the field properties at the bottom of the screen, switch to the Lookup tab, and change the Display Control to Check Box. d. Do this for the Surveys.Complete and Riders.Subscribed fields. 2) Saved Import Forgets your Primary Key Choice a. I don t know why this happens, but it does when you select an existing field as your primary key.

9 b. If you run a saved import, make sure you check that your primary key field is correctly specified. ADVANCED QUERY DESIGN There are two main types of queries: SELECT (selects certain records) and ACTION (manipulates or changes data or tables). SELECT QUERIES EXPLORING CRITERIA Queries allow you to retrieve very specific information from your database, but you have to know how to ask the right question. This means you need to understand your database structure (tables, fields, and relationships) and how to use criteria syntax. SORTING RESULTS To sort the results of your query according to a field or combination of fields, use the Sort row in the query design grid. If multiple fields are used for sorting, records will be sorted in field order from left to right. For example, if you want to sort by Last Name and then by First Name, make sure that the Last Name field is on the left. {EXERCISE: Sort Surveys by TransitMode and then by TimeSent. Also include the Rating in the query results.} Design:

10 AND VS. OR Very complex queries might require several criteria to be treated as options or as multiple refinements. For example, you may want all surveys from either Light Rail or Metro. This is an OR statement. OR statements increase the number of results. On the other hand, you may want all surveys from Light Rail from January This is an AND statement (TransitMode = Light Rail AND TimeSent is in the January 2013 range.) AND statements reduce the number of results. Access Queries have multiple OR rows in the design area. Any criteria placed on the same row are treated as AND statements. Criteria on different rows are treated as OR statements. Let s look at this example: There are two criteria on different rows: 1) TransitMode = Bus 2) Rating < 3 These criteria will work as an OR statement: Please give all surveys that are either from Bus or where Rating was less than 3. This returns 12,837 surveys. To only see records from Bus where the Rating was less than 3, move the <3 criteria to the same row as the Bus criteria. This query returns only 5,634 records, because to meet the criteria, the survey has to be from the Bus TransitMode AND the Rating has to be less than 3.

11 CRITERIA SYNTAX 1) For all data types, if you want to find all records with a SPECIFIC (EXACT) VALUE, simply type that value into the criteria box 15 find all records with a value of 15 Wilson find all records with a value of Wilson (Access will change this statement to Wilson because it knows it is text) 2/3/2008 find all records that have a date of 2/3/2008 (Access will change this statement to #2/3/2008# because it knows you re talking about a date) Yes find all records that have a value of Yes (for Yes/No data types, Access will leave Yes as it is; for text data, Access will change this to Yes, because it is a string of text) 2) For all data types, if you want to find records that match a DISCRETE SET OF VALUES, you can use the In operator In(10,12,14,16) find all records with a value of 10, 12, 14, or 16 In( PA, MD, NJ, VA ) find all records with a value of PA, MD, NJ, or VA (Notice the quotes surrounding the options; these must be added for Access to treat the options like text.) 3) For any numerical data (including dates, the following syntax can be used) where you want a RANGE OF VALUES: <15 find all records with a value less than 15 >15 find all records with a value greater than 15 <>15 find all records with a value that is not 15 (can also use Not 15) Between 15 And 20 find all records with a value between 15 and 20, inclusive Between #1/1/2008# And #1/31/2008# find all records with a date in January ) To EXCLUDE A VALUE, SET OF VALUES, OR RANGE OF VALUES, use the Not operator Not 15 find all records that are not equal to 15 (equivalent to <>15) Not Wilson find all records that are not Wilson (Access will change to Not Wilson ) Not Between #1/1/2008# And #1/31/2008# find all records that are not in January of 2008 Not In( PA, MD, NJ, VA ) find all records that are not equal to PA, MD, NJ, or VA 5) To create a WILDCARD (OR FUZZY) SEARCH, use the Like operator and the wildcards (* or?) Like W* find all records that begin with W and are followed by anything Like *W find all records that end with W and begin with anything Like *W* find all records that contain a W Like W?? find all records that start with a W that is followed by 2 characters Additional Notes on Criteria Syntax: 1) When working with Date/Time fields, you may need to include both a date AND time in your criteria if the data contain times. For example, to see all January 2013 ratings, you should use the statement: Between #1/1/2013# And #1/31/ :59:59 PM#. If you don t type a time in your criteria (i.e., you only provide a date), Access assumes you mean 12:00 AM at the start of that date. This misses 24 hours of data. 2) Other special criteria: a. Is Null: values where the field is empty b. Is Not Null: values where the field is not empty

12 USING RELATIONSHIPS IN QUERIES Defining relationships between tables allow us to leverage additional tables in our queries very easily. The act of adding an additional related table to a query will AUTOMATICALLY filter your results to only show records that have matching related data in BOTH tables. For example, adding the BusRoutes table to our query design (drag and drop the table from the navigation pane to your query design), will add another criteria to your query: Show me only those records that have a bus route that appears in BOTH tables. This is a great, simple way to check for data validity and to clean out incorrect or invalid responses. You can also place a criteria on a field in the related table to filter records in your other table(s). Add the Type field from the BusRoutes table to your design grid, and add the criteria QuickBus. Running the query reveals 251 VALID ratings with a Rating score of less than 3. {Assignment: Try creating a query that only shows those ratings received from currently subscribed riders.} SPECIAL SELECT QUERIES You can retrieve your records in different ways. You can calculate totals from records that meet your criteria, you can prompt the user for a value to use in your criteria statements, and you can retrieve only a certain number of records (e.g., the top 5%). CALCULATING TOTALS IN QUERIES A query that aggregates (summarizes) your data is called a Totals Query. Totals queries group similar records together (e.g., the same customer) and then calculate a total on a given field (e.g., sum the sales). This query would give you the TOTAL sales PER customer.

13 Let s say you have sales data in a table: Date CustomerID SaleAmount 9/24/ $ /24/ $ /25/ $ /25/ $ /26/ $40.00 And you want to know the total sales per customer. You would create a TOTALS query to group the records by CustomerID and then sum the SaleAmount. The results would look like this: CustomerID SumofSaleAmount 1 $ $62.00 To turn a basic SELECT query into a TOTAL query, you simply have to: 1) Create Queries Query Design 2) Add the tables you need for your query 3) Design Show/Hide Totals ( ) 4) Clicking on the Totals ( ) button will add the Total row to your query design grid. 5) Add the fields you need for your query. 6) Determine what Totals operation you need to perform on each field

14 a. Group By: uses the field to create groups of records. This is usually the per part of an analysis. For example, sales per CUSTOMER means group by a field to uniquely identify customers; surveys per PRODUCT means group by a field to uniquely identify products; complaints per MONTH means group by a field that contains months. b. Sum: calculate the sum of a field for each grouped set of records c. Avg: calculate the average of a field for each grouped set of records d. Min: calculate the minimum value for each grouped set of records e. Max: calculate the maximum value for each grouped set of records f. Count: count the number of records included in each grouped set of records (IMPORTANT: count only counts the number of records that contain data in the field you are counting. If there are blank records, they will not be included in the count. I usually recommend counting on primary key fields to avoid undercounting.) g. StDev/Var: Standard deviation or variance h. First/Last: Find the first or last record in the group, depending on how the query is sorted. i. Expression: use a user-defined mathematical expression j. Where: uses the indicated field only as a criterion for which selecting records are to be totaled but disregards the field in the process of totaling. Date fields are often used in totals queries to select the records that you want to perform the analysis on. For example, count the number of sales per customer in January Field Date CustomerID SalesID Total Where Group By Count Criteria Between #1/1/2013# And #1/31/2013# {Try it! Create a query to calculate the average rating per Bus Route type (only include valid Bus Routes in the query)} {Try it! Create a query to calculate the average rating and number of ratings per Bus Route type (only include valid Bus Routes in the query) for the year 2012} Additional Notes about Totals Queries 1. The query will always retrieve the live data, so, any time the data changes, the query results will change 2. Blank values will not count in the aggregate functions or expressions that you have provided RETRIEVING A CERTAIN NUMBER OF RECORDS You may only want to see the top 5 (or top 5%) of records rather than seeing all results. Queries that only display a certain number of percentage of records are called Top Values queries. These queries reduce the total number of rows that are returned in your query results to reflect an absolute number of records or a percentage of records taken from the top of the result set. 1. In query Design View 2. Design Query Setup Return 3. Pick your desired number of records to return or type in your own (can be absolute number of records or a percentage of records)

15 Only 5 records Sorted by Rating in descending (highest at top) 4. SORT your query results so that the records you want are at the TOP of your query. {Try it! Find the top 5 bus routes based on average rating.} {Try it! Find the lowest 10% satisfied riders based on average rating.} PROMPT YOUR USER FOR A CRITERIA VALUE Queries can have criteria values hard coded (typed directly into the Criteria row of the query design) OR, you can ask your user to type the requested value to make your query flexible and able to extract different ranges of dates, different target values, etc. This is called a Parameter Query. When you make a Parameter Query, you create a placeholder criteria that will ask the user for input every time the query is run. For example, create a query that retrieves all records with last names that begin with [criteria]. 1. In query design 2. In the criteria row under the desired field in the design grid, type the following (replace message here with your user prompt, e.g., [Enter Bus Route] [Message Here] 3. Edit the query as desired 4. Save the query 5. Run the query 6. Notes: i. You can specify MANY parameters for your queries, the more parameters you specify, the more prompts will be generated. ii. If the user does not type a value in the prompt box, Access will look for null values in the table to match against. If you wish to allow your user to bypass your criteria to select ALL records, then type the following:

16 Like * & [Message Here] & * iii. Parameter queries can be used with other operators (Like, Between And, etc.) {Try it! Make a query that shows all surveys received from a given bus route. The query should prompt the user for the desired bus route number.} {Try it! Make a query that calculates the total number of ratings received per bus transit mode between two dates. The query should prompt the user for the date range.} ACTION QUERIES ALTER OR MANIPULATE THE DATA IN YOUR TABLES(S) 1. Make Table: takes the records and fields you ve specified from one table or query and creates a new table (or overwrites and existing table) with the selected data a. Create a Select Query that meets your criteria b. Design Query Type Make Table c. Provide the name of the table that will be made when you run the query d. Save the query e. Run the query {Try it! Create a query that will put all incomplete surveys into their own table.} 2. Delete: deletes records from the chosen table that match the given criteria a. Create a Select Query that will select the records you want to delete

17 b. (You only need to design your query to select the particular field(s) upon which you will place your deletion criteria. c. Design Query Type Delete d. Save the query e. Run the query {Try it! Make a query to delete the incomplete records from the Surveys table.} 3. Append: take the records and fields you ve specified from one table or query and adds them to an existing table. a. Create a Select Query that meets your criteria b. Design Query Type Append c. Select the table to which you want to append your data (you can specify to which field in the destination table you want each field in the source table to append to; however, if your field names match exactly, Access will provide the information for you) d. Make sure the Append To: row in the design grid contains the correct field names for the destination table. e. Save the query f. Run the query

18 {Try it! Append the incomplete records back onto your Surveys table.} 4. Update: updates field values for records that meet your criteria a. Create a Select Query to select the records you wish to update based on a field(s) (if applicable) b. Design Query Type Update c. In the Update To: row in the design grid, type in the value or formula that to create the new values for that specific field. d. Run the query e. Save the query {Try it! Create a new field in your Surveys to hold the hour the survey was sent. Use and update query to calculate the hour and insert it into each record.}