Create a Database Model (also known as Entity Relationship diagram)To start your database model diagram, do one of the following: Create a new model diagram from scratch. If you don't have an existing database that you want to use as a starting place, you can start with a blank Database Model and add your own tables and relationships.
On the File menu, point to New, point to Software and Database, and then click Database Model Diagram. On the Database menu, point to Options, and then click Document. In the Database Document Options dialog box, select the symbol set that you want to use and other table and relationship options, and then click OK. Use an existing database as a starting point. If you have a database that you want to model so that you can understand it better or use it as a starting place for a new model, you can use the Reverse Engineer Wizard to extract the schema, or structure, of the database and build a new model. Note Before you start the wizard: If you are reverse engineering a Microsoft Office Excel workbook, before you start the wizard you need to open the workbook and name the group (or range) of cells that contains the column headings.
If you want to use more than one worksheet, just name the group of column cells in each worksheet. These ranges are treated like tables in the wizard. For more information about how to name a range of cells, see the topic in your Microsoft Office Excel help titled Define named cell references or ranges. For best results, set your default driver to the target database that you want to reverse engineer before you run the Reverse Engineer Wizard. This step ensures that the wizard maps the native data types correctly and that all the code that is extracted by the wizard is correctly displayed in the Code window. On the File menu, point to New, point to Software and Database, and then click Database Model Diagram. On the Database menu, click Reverse Engineer.
On the first screen of the Reverse Engineer Wizard, do the following: Select the Microsoft Office Visio database driver for your database management system (DBMS). If you have not already associated the Visio database driver with a particular ODBC data source, click Setup. Note If you are reverse engineering an Excel worksheet, choose the ODBC Generic Driver.
Select the data source of the database that you are updating. If you have not already created a data source for the existing database, click New to do so now. When you create a new source, its name is added to the Data Sources list.
When you are satisfied with your settings, click Next. Follow the instructions in any driver- specific dialog boxes. For example, in the Connect Data Source dialog box, type a user name and password, and then click OK. If your data source is not password protected, just click OK. Note If you use the ODBC Generic Driver, you may receive an error message that indicates that the reverse engineered information may be incomplete.
In most cases, this is not a problem — just click OK and continue with the wizard. Select the check boxes for the type of information that you want to extract, and then click Next. Note Some items may be unavailable (appear grayed out) because not all database management systems support all the kinds of elements that the wizard can extract. Select the check boxes for the tables (and views, if any) that you want to extract, or click Select All to extract them all, and then click Next.
Note If you are reverse engineering an Excel worksheet and don't see anything in this list, it is likely that you need to name the range of cells that contains the column headings in your worksheet. If you selected the Stored Procedures check box in step 5, select the procedures that you want to extract, or click Select All to extract them all, and then click Next. Select whether you want the reverse engineered items to be added automatically to the current page.
← What is Microsoft Access? How To Create A New Table In Access. How To Open Up The Entity Relationship Diagram In Access. I have database scheme for Microsoft Access. MS Access ER diagram. The other option is to create your own ER Diagram without an importation via some free. With the Database Model Diagram template, you can create a new model or. Model Diagram template. Microsoft Office Visio. access the same information.
Note You can choose to have the wizard automatically create the drawing, in addition to listing the reverse engineered items in the Tables and Views window. If you decide not to have the drawing created automatically, you can drag the items from the Tables and Views window onto your drawing page to manually assemble the database model.
Review your selections to verify that you are extracting the information that you want, and then click Finish. The wizard extracts the selected information and displays notes about the extraction process in the Output window. Import and refine an existing model. If you have an existing Visio.
Modeler or PLATINUM ERwin model, you may be able to import it to create a Visio database model diagram. This ability is limited to only Visio. Modeler 2. 0 or later dictionary model (. PLATINUM ERwin 2. On the File menu, point to New, point to Software and Database, and then click Database Model Diagram.
Creating Entity Relationship Diagrams (ERDs). Create the Microsoft Access ODBC data source. Creating Entity Relationship Diagrams (ERDs) for ServiceCenter. Entity Relationship Diagram for MS Access. I haven't much experience of Access. I've got into the habit of using ER diagrams to. Entity Relationship Diagram. Microsoft Access includes a diagram utility that. How to Make an ERD in Access. Microsoft Access includes a diagram utility that lets you create and view an.
On the Database menu, point to Import, and then click Import < model type>. Type the path and file name for the model that you want to import, or click the Browse button to locate the model file, and then click Open. In the Import dialog box, click OK. Visio imports the file and displays its progress in the Output window. The imported tables are displayed in the Tables and Views window.
In the Tables and Views window, select the tables that you want to model, and then drag them onto the drawing page. After you create a database model diagram, the work of refining the diagram begins. You can add and customize tables and views, create relationships, and customize columns and data types. Tables. Use the Entity shape to create a table in your diagram. From either the Entity Relationship or Object Relational stencil, drag an Entity shape onto the drawing. Double- click the shape to open the Database Properties window. Under Categories, click Definition and type a name for the table.
Under Categories, click Columns, type a name, and choose a data type. Select the Req'd check box for columns that can't have null values. Select the PK (primary key) check box for columns that uniquely identify each row in the database table. Under Categories, click Indexes, Triggers, Check, or Extended to create these optional elements. Columns. Use the Database Properties window to add or change properties for columns, including data types and primary keys. Double- click the table in your diagram. In the Database Properties window, under Categories, click Columns.
Click in the first empty Physical name cell, and type a name. To change the data type for a column, click the column's Data Type field, and then select a data type from the list or type it into the list. For example, you can type decimal(8,2) or char(3. To prevent null values, select the Req'd check box. To specify that the column is a primary key, select the PK check box. To see more column properties in addition to those that appear when you click the Columns category, select the column and then click Edit. Relationships. Relationships use primary and foreign keys to allow databases to match a row in one table with a row in a related table.
You can show those relationships in your diagram. In addition, you can set their cardinality (for example, one- to- many) and use either Crow's feet, Relational, or IDEF1. X notation to show the cardinality.
You can't show many- to- many relationships with any of these notations in the Database Model Diagram template. Create a relationship between tables: Make sure that both tables are visible in the diagram. If you reverse engineered the model from an existing database, you may need to drag one or both from the Tables and Views window onto the drawing page. Double- click the table that you want for the primary key side of the relationship. In the Database Properties window, under Categories, click Columns. In the grid, click the column that you want to use to uniquely identify each row in the table, and select the PK check box to set it as the primary key.
From the Object Relational or Entity Relationship stencil, drag a Relationship shape and drop it onto a blank space on the page. Connect the higher end to the table with the parent table. Connect the other end to the child table.
If the second table doesn't already contain a column with the same name as the primary key, the modeler adds it to the second table as a foreign key. Note If relationship lines disappear, on the Database menu, point to Options, and then click Document. On the Relationships tab, under Show, select the Relationships check box. Set the relationship's cardinality: Double- click the relationship. In the Database Properties window, under Categories, click Miscellaneous. Under Cardinality, choose the cardinality that best fits the relationship. For one- to- many relationships, the best choice is either Zero or more or One or more.
For one- to- one relationships, the best choice is either Zero or one or Exactly one. To make other refinements to your diagram (such as creating indexes, check clauses, and triggers) you can do the following: Create indexes. Indexes improve the performance, or speed, of your database when you run a query. Open the database model diagram. Double- click the table to which you want to add an index, and in the Database Properties window, in the Categories list, click Indexes. Click New. In the Create Index dialog box, type a name for the index, and then click OK.
In the Index Type list, select an option to create a unique or non- unique index. In the Available Columns list, select the name of each column that you want to include in this index, and then click Add >. In the Indexed Columns list, select the Asc check box to create an index that has an ascending sort order, or clear the check box to create an index that has a descending sort order. The database model diagram is updated. Create views. You can think of a view as a saved query. Views are particularly handy if you need to repeatedly access the same information from multiple tables, or if you want to expose the data to users without letting them change the actual tables.
Example of creating an Access 2. Database from an Entity Relationship Diagram.
This short video works with the example we discussed in class on Thursday, Feb 3. It takes you through what an ER diagram (as we are using them in our class) looks like, and then opens Access and creates a database. The video shows you how to create a table in your new database, based on the ER diagram.
Of course, this diagram is not the same as the one you will be designing for Lab.