FAQ / Guides

Frequently asked questions (FAQ)

Review frequently asked questions about CA's ERwin® Data Modeling line of products, Sandhill's services and solutions, and general data modeling and data management topics.

ERwin FAQ's

Q. How do I infer relationships automatically when reverse engineering a DBMS

A. See the enclosed steps.

Q. How do I hide relationship lines in the physical diagram

A. See the enclosed screen shots for steps.

Q. I have 1 model that is quite large (27,626 K) and if I make a bunch of updates, save the model and try to run this report, it cannot create the pictures for the HTML model (table and view sections contain data). However if I save my changes and close down ERwin then reopen it, the report will generate. I believe this maybe a memory issue, since ERwin stores a list of changes.

A. There are some known issues when reporting from large models particularly if graphics need to be generated. It is safer to save the model before running such reports. The ODBC interface due in ERwin r.7.3 will be a big step forward for reporting but it will not generate graphics. In addition V7.3.10 has additional benefits regarding memory consumption.

Q. How can we convert 4.1 data model into 7.2 ? (We have some older models in version 4.1 we need to upgrade.)

A. Here are the high level steps—You will need to convert your V4.1 models into V4.1.4 models which can then be read by r7.2. You can work with ERwin data models from version 4.1.4 in r7.2. When you open a 4.1.4 model for the first time in r7.2, there is a one-time performance cost to convert the 4.1.4 model to the new r7 format. (i.e. it will take a longer time than just opening an r7.2 model.)

Q. We want to be able to publish data models on a web. Is there an ‘export' mechanism, or some other way of exporting our models to a web page on our intranet?

A. Yes the reporting functionality will allow you to publish to the web in several formats. Open any model, and via the Tools /Report builder on the menu select Report Builder, then click new to create a new report. by double clicking you will see all the supported types.

Q. What is the recommended method to accomplishing version control and check in and check out functionality? Can we use Microsoft Visual Source Safe?

A. The best way it to leverage version control and Check in / out is via CA's ERwin Model Manager, this is what the product was designed for. Please see the ERwin Model Manager data sheet for more information. A solution like Microsoft Visual Source Save or other versioning solutions will only provide basic functionality, compared to ERwin's Model Manager.


Model Manager FAQ's

Q. Where can I find information on ERwin Model Manager Architecture?

A. Installing and configuring ERwin Model Manager are two separate processes. To install ERwin Model Manager you have to have right to the DBMS that you wish to install into. The install is the easy part. Configuring ERwin Model Manager is where clients will need advise on how best to set up, security, libraries and roles.  Click on the following link to view a highlevel ERwin Model Manager Architecture.

Q. How can I improve the performance of Model Manager V7.x?

A.There are many parameters that one must review. Sandhill has put together a 9 page document, that pulls together information from several sources including our own experience on how to improve the performance of ERwin Model Manager in V7.x. Click on the link to view this information.

Q. If a client has many Model Manager licenses for example 10, does this mean that we would be allowed 10  Model Manager Server Repositories installed?  Or is there a limited to the  number of concurrent ERWIN Data Modeler users that can be accessing one or more Model Manager Server Repository at any given point in time?

A. The number of Model Manger licenses does not limit the number of repositories a company can have, but limits the number of named users who can access those repositories.  If a client has 10 model manager licences then a total of 10 users can access any number of repositories. If a license is used by User A on one repository, only user A can use that licence to access other repositories in the company.

Q. I have a user with a SQL server user account (db_Writer) which is assigned to two libraries as viewer and one library as a data modeler.  My question is why does the user see all the other libraries and therefore he can open them (Read-only). I would like to hide these libraries from his account ?

A. MM does not have the ability to hide a library or models within a Model Manager repository.  Once a user is established the minimum rights of the role “user” they have access to read-only to ALL.  So this mean there is no way to hide any model within that Model Manager repository. 



Download guides to using CA's ERwin® Data Modeling line of products with other popular products and technologies.

Deploying (Forward Engineering) Emovies to SQL Server 2005

This scenario shows how Erwin could be used to create, maintain and synchronize the sample emovies data model in an SQL server 2005 environment.

Guide to Reverse Engineering using ERwin 7.x

ERwin is a robust Database modeling solution providing 5 Key areas of support for data modeling professionals.