Converting a Model into another Type
All the work that you put into the Conceptual model need not go to waste. We can utilize it as the basis for the Logical model.
- Select File > Model Conversion... from the main menu to open the Convert to New Model dialog.
- Choose Logical as the Model Type and click OK:
Convert to New Model
Note that the Target Database dropdowns are disabled because a Logical model does not contain database-specific information.
Navicat Modeler will create a new Logical Model of the Sales Star Schema. Entities and their relationships will be carried over, so that we can dive right into attribute (a.k.a. field) creation.
Here are the attributes for each of the four entities:
t_sales:
|
Name
|
Type
|
(Char) Length
|
Decimals*
|
Not Null
|
Default Value**
|
|
id (PK)
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
date_id
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
store_id
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
product_id
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
units_sold
|
INTEGER
|
0
|
0
|
No
|
NULL
|
*Decimals only apply to numeric fields.
** Can be either NULL or an EMPTY STRING.
t_dates:
|
Name
|
Type
|
Length
|
Decimals
|
Not Null
|
Default Value
|
|
id (PK)
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
day
|
CHAR
|
2
|
0
|
No
|
NULL
|
|
month
|
CHAR
|
2
|
0
|
No
|
NULL
|
|
year
|
CHAR
|
4
|
0
|
No
|
NULL
|
|
quarter
|
NUMERIC
|
1
|
0
|
No
|
NULL
|
t_stores:
|
Name
|
Type
|
Length
|
Decimals
|
Not Null
|
Default Value
|
|
id (PK)
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
store_num
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
name
|
CHAR VARYING
|
255
|
0
|
Yes
|
N/A
|
t_products:
|
Name
|
Type
|
Length
|
Decimals
|
Not Null
|
Default Value
|
|
id (PK)
|
INTEGER
|
0
|
0
|
Yes
|
N/A
|
|
prod_code
|
CHAR VARYING
|
25
|
0
|
Yes
|
N/A
|
|
name
|
CHAR VARYING
|
255
|
0
|
Yes
|
N/A
|
|
prod_category
|
CHAR VARYING
|
50
|
0
|
Yes
|
N/A
|
The Converted Sales Star Schema Model
- The easiest way to define an entity’s attributes is to right-click it and choose Design Entity from the popup menu.
That brings up the Entity Design dialog. It provides tabs for managing attributes (fields), indexes, relations, uniques, and comments:
t_dates - Entity
The Completed Sales Star Schema Logical Model
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