ACC: Sample Table Design to Support Questionnaire Applications

MORE INFORMATION

The following examples outline nonrelational table design commonly used for questionnaires and surveys and suggests an improved, relational table design.

Nonrelational Table Design

When designing tables for questionnaire applications, many users begin with a design that resembles the table below. Each record contains multiple fields, called Question1 through Question<n>, that contain responses to the questions.

   Table: Table1 (old)
   --------------------------------------
   FieldName: Respondent ID [Primary Key]
   FieldName: Question1
   FieldName: Question2
   FieldName: Question3
   .
   .
   .
   FieldName: Question<n>
				

Problems occur when you want to perform crosstab queries to summarize and/or graph the questionnaire results.

Relational Table Design

A relational table design better supports summary queries, reports, and graphs. In the table below, the Question ID field identifies the question and the Response field contains the answer.

   Table: Table2 (new)
   ----------------------------------
   Field: Respondent ID [Primary Key]
   Field: Question ID   [Primary Key]
   Field: Response
				

How to Switch to Relational Database Design

To convert data that has been entered in Table1 format, follow these steps:

1. Create Table2 according to the above structure, using the following data type criteria:
   
   
   1. All Respondent ID fields must be the same data type.
   2. The Question ID field must be a Text data type.
   3. The Response field must be the same data type as the Question<x> data types.
2. Create a new query based on Table1.
3. From the Query menu, choose Append Query (Append in versions 7.0 and earlier) Select Table2 as the table to which you want to append the data. Design the query as follows:
   

         Query: Query1
         ---------------------------
         Field: Respondent ID
            Append To: Respondent ID
         Field: Question1
            Append To: Response
         Field: "Question1"
            Append To: Question ID
   						

4. Run Query1 to append to Table2 each participant's responses to Question1.
5. Repeat steps 2-4 above, replacing Question1 with Question2, and "Question1" with "Question2". You must re-create or modify this query for each question in Table1.
6. After running all the append queries, the result is a table (Table2) that can easily summarize your results in a crosstab query:
   

         Query: CrossTabExample
         ---------------------------
   
         Field: Question ID
            Total: Group By
            Crosstab: Row Heading
         Field: Response
            Total: Group By
            Crosstab: Column Heading
         Field: Response
            Total: Count
            Crosstab: Value