ACC2000: Sample Table Design to Support Questionnaire Applications (209493)

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 following table. Each record contains multiple fields, called Question1 through Question<n>, that contain responses to the questions.

   Table: Table1 (old)
   --------------------------------------
   FieldName: RespondentID [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 following table, the Question ID field identifies the question and the Response field contains the answer.

   Table: Table2 (new)
   ----------------------------------
   Field: RespondentID [Primary Key]
   Field: QuestionID   [Primary Key]
   Field: Response
				

How to Switch to Relational Database Design

Steps Using an Access Database.

1. Create the following table structure:

      Table: Table2
      ----------------------------
      Column Name: RespondentID
      Datatype: Integer
   
      Column Name: QuestionID
      Datatype: text
   
      Column Name: Response
      Datatype: yes/no
   
      Table Properties: Table2
      -------------------------------
      PrimaryKey: RespondentID, QuestionID
   					

2. Create a new query based on Table1.
3. On the Query menu, click Append Query. Select Table2 as the table to which you want to append the data. Design the query as follows:

         Query: Query1
         ---------------------------
         Field: RespondentID
         Append To: RespondentID
         Field: Question1
         Append To: Response
         Field: "Question1"
         Append To: QuestionID
   					

4. Run Query1 to append to Table2 each participant's responses to Question1.
   
   Repeat steps 2 through 4, replacing Question1 with Question2, and "Question1" with "Question2". Modify and run this query for each question in Table1.
5. After running all the append queries, the result is a table (Table2) that can easily summarize your results in a totals query:

      Query: qryResults
      ---------------------------
   
      Field: QuestionID
      Table: Table2
      Total: Group By
   
      Field: Ayes: Abs(Sum([Response]=Yes}}
      Total: Expression
   
      Field: Noes: Count([Response]) + Sum([Response]=Yes)
      Total: Expression
   
   					

Steps Using an Access Project.

1. Create the following table structure:

      Table: Table2
      -------------------------
      Column Name: RespondentID
      Datatype: int
   
      Column Name: QuestionID
      Datatype: nvarchar
   
      Column Name: Response
      Datatype: bit
   
      Table Properties: Table2
      ------------------------------------
      PrimaryKey: RespondentID, QuestionID
   					

2. Create and run the following stored procedure:

      Create Procedure StoredProc1
      AS
      INSERT INTO Table2 (RespondentID, Response, QuestionID) 
      SELECT Table1.RespondentID, Table1.Question1, 'Question1' AS Expr1
      FROM Table1
   					

3. Edit and then run StoredProc1 for each Question. For example, the stored procedure for the second question would read:

      Alter Procedure StoredProc1
      AS
      INSERT INTO Table2 (RespondentID, Response, QuestionID) 
      SELECT Table1.RespondentID, Table1.Question2, 'Question2' AS Expr1
      FROM Table1
   						

   Note that the keyword "Create" is used in the initial instance; the keyword "Alter" is used in subsequent instances.
4. To display the number of positive responses, create and run the following stored procedure:

      Create Procedure Ayes
      As
      SELECT QuestionID Question, COUNT(ALL QuestionID) [Yes count]
      FROM Table2
      WHERE Response = 1
      GROUP BY QuestionID
   					

5. To display the number of negative responses, create and run the following stored procedure:

      Create Procedure Noes
      As
      SELECT QuestionID Question, COUNT(ALL QuestionID) [No count]
      FROM Table2
      WHERE Response = 0
      GROUP BY QuestionID