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In this lesson, we will now look at "fine tuning" the dictionary in the Dictionary Editor. This will directly affect how our application will be generated in Lesson Eight.

1.Highlight the //Customer// table and examine the **Fields** list. You should notice a //State// column. In the next sequence of steps, we will create a lookup table to allow a user to select from a list of valid state abbreviations. After that, we will "notify" the state column that a lookup is active.

2.In the DCT Explorer, highlight the Tables entry, and press the **Add Table** {{addtable.jpg|AddTable.jpg}} button, located in the DCT Explorer toolbar.

{{addtabledialog.jpg|AddTableDialog.jpg}}

3.In the **Label** entry, enter //States// in it, and then press the TAB key.

4.Press the TAB key again to accept //Sta// as the Prefix.

Next, you are prompted to choose a Table Driver.

5.Verify or select //TOPSPEED// from the **Driver** drop list, and press the TAB key.

6.Press the **OK** button to complete the new Table.

7.In the //Fields// //Quick View// pad, press the **Add **{{addtable.jpg|AddTable.jpg}} button, located in the toolbar.

{{newcolumn.jpg|NewColumn.jpg}}

8.Type //State// in the first row of` the **Column Name** entry, and press the TAB key.

{{columnname.jpg|columnName.jpg}}

This creates a column named //State//. This column is the link to the State column in the Customer table. Using the same column names makes it easier to link the two tables in a relationship. In the generated Clarion code, adding the table's prefix to column labels (separated by a colon) creates unique names for columns with the same name in separate tables. Therefore, this column will actually be called STA:State, while the column in the Customer table is called CUS:State.

{{notebox.jpg|NoteBox.jpg}}

Clarion also fully supports a naming convention called [[field qualification.htm|Field Qualification Syntax]]. The prefix format above (STA:State) can also be represented as //States.State// (//file label//.//field label//).

9.In the **Characters** entry, type //2//, or use the spin control, and press the TAB key.

{{f1characters.jpg|F1Characters.jpg}}

**10.****Accept all other defaults, and press the ****OK**** button to complete the new column.**

**At this time another Column Properties dialog opens allowing you to enter a second column.**

11.In the **Column Name** column, type //StateName//, and then press the TAB key.

12.In the **Characters** column, type //30//, then press the OK button to complete this column.

13.At this time another //Column Properties// dialog opens allowing you to enter a third column. We are finished with this table's columns, so press the **Cancel** button to exit this dialog.

{{aftercolumns.jpg|aftercolumns.jpg}}

14.Next locate the //Keys// Pad, and press the **Add **{{addtable.jpg|AddTable.jpg}} button, located in the toolbar.

{{keyspad.jpg|KeysPad.jpg}}

**15.****In the ****Label**** column, Type ****//StateKey//****.**

**16.****In the Attributes group, check the ****Require Unique Value**** check box.**

This specifies a key that does not allow duplicate entries, enabling you to have a unique state reference file for your customers. This allows us to create a Many to One relationship between the two tables (Many Customers live in one State).

17.Click on the **Columns** tab, and press the **Add **{{addtable.jpg|AddTable.jpg}} button, located in the toolbar. In the //Select a Column// dialog, highlight State and press select as shown below:

{{addcolumntokey.jpg|AddColumnToKey.jpg}}

18.Press **Cancel** in the //Select a Column// dialog to close this window, and press the **OK** button to save this key. Finally, press **Cancel** again in the Key Properties dialog to stop adding additional keys and return to the main Dictionary IDE.

{{dctafterkey.jpg|DCTAfterKey.jpg}}

19.Press the **Save** button {{savebutton.jpg|savebutton.jpg}} in the IDE toolbar at this time to save your work, and stay in the Dictionary Editor.

[[exercise six create the lookup relationship.htm|Exercise Five - Create the Lookup Relationship]]