ER/1, the newcomer on the block, was just released by Embarcadero Technologies (the creators of DBArtisan and other database administration tools) in March 1996 but appears to be a well-developed program.
The simple installation uses Install Shield, and after three diskettes you are up and running. Once you click on the ER/1 icon you are confronted with an inviting user interface. The thought that went into the product is obvious when you click on File-New. You are then prompted to create a new ER model and are given a pulldown box of supported target databases, or you can select to reverse-engineer a database. If you choose to create a new ER model, you see a blank sheet and a minimal number of icons on the toolbar, which is a refreshing change from some programs that stick so many icons up on the toolbar that they become confusing. You are greeted by a well-designed floating toolbox that gives you quick access to the normal entity creation and relationship definition commands. Overall, this is a nice work area for serious data-modeling work. The online help is useful and provides quick assistance. However, the manual tends to be feature-oriented and not as rich in explanations of "the hows and the whys" as is the ERwin/ERX manual.
ER/1 only supports IDEF1X notation; in fact, it is designed for IDEF1X from the ground up. So if you need other notation support, look elsewhere. Otherwise ER/1 is a great data-modeling tool. If I had to describe using ER/1 in a single word, I would pick "easy." I found myself continually drawn to using ER/1 rather than ERwin/ERX and other CASE tools, despite ER1's youth.
Like ERwin/ERX, ER/1 has the GoTo option, which is a great way to jump to an entity without having to scroll through your data model. One thing I did find myself doing when I used GoTo was typing the first letter of the entity that I wanted to find (such as "c" for customer). I would then naturally try using the cursor down key to choose among the entities that start with a "c." However, ER/1 does not let you do this, so I found myself repeatedly hitting the cursor down key for nothing. It seems like they could support such a shortcut.
Aside from the normal basic data-modeling features such as specifying rules, defaults, user-defined data types, triggers, indexes, and stored procedures, ER/1 supports some features that you might not expect. You find support for subtype clusters and supertypes that are an advanced entity relationship. The reporting tool can generate both detailed and summary reports about entities, attributes, relationships, and supertypes.
If you have a team of database modelers that need to share a data model, you should be aware that there is currently no support for version control in ER/1. You should see this added in version 2.0 with support for both Intersolv's PVCS and MKS version control. ER/1 does support a good selection of target databases, including Microsoft SQL Server 6.0 and 4.2, Sybase 11 and 10 and SQL Anywhere, Oracle7, DB2, SQLBase, Watcom, and Informix SE and Informix On-Line.
ER/1 is MDI-compliant, so you can have multiple models open and copy between them. Because ER/1 is a 32-bit application written with Win95 and Windows NT in mind, you must have a 32-bit ODBC driver for your target server. When selecting ODBC drivers, keep in mind that a 16-bit ODBC driver will not work correctly. I like the fact that ER/1 supports long file names, which can help in distinguishing different models. Subsetting of your large data model is also supported, as are detailed reporting features. When you generate the SQL for your database, you can choose between generating triggers or using referential-integrity constraints (assuming your target database server supports this). Version 1.1 of ER/1 came to a screeching halt when I tried to modify tables with cascading referential constraints. I complained to Embarcadero and it fixed the problem with version 1.12 of ER/1.
I was surprised to see that reverse-engineering is supported. I expected to find this in only a more expensive product. ER/1 is able to reverse-engineer tables, constraints, primary and foreign keys, defaults, rules, and indexes. You can also specify that system tables for the target database also be reverse-engineered. (See Figure 2)
Printing support is very good. The print window lets you see the overall print area and you can resize printouts. You can also select a range of pages to print. Unlike ERwin/ERX, you are limited to printouts of 100 inches by 100 inches (about 83 square feet). One thing I do not like about the printing is that the printed pages do not overlap, but rather they butt up to each other after you trim off the top and side margins. It would be nice if you could specify an overlap, as this would eliminate the need for a paper cutter.
No Undo! Okay, I will say it again, Undo must be supported - better yet, add multiple-level Undo support! Lack of support for Window 3.x was glaring but, by the time you read this, the Embarcadero folks should have version 1.2 available with Win32s support that will let Windows 3.x users use ER/1. Also, when editing a column it would be useful to have a Next/Previous button to make changing the values of several attributes simpler. I was able to declare a column that was data type bit and allowed nulls. ER/1 should have caught this and prevented it, although ERwin/ERX failed the same test. Also lacking is integration with other front-end development tools such as Visual Basic or PowerBuilder.
While Embarcadero does have a CompuServe email address for tech support (72274,2173), the absence of a users forum is a small minus in my book. But thanks to the increasing popularity of interactive Web sites, the need for a CompuServe forum is steadily diminishing. Embarcadero's ER/1 comes with 60 days of free technical support. After that period, you pay $150 per user per year.
Both vendors have Internet Web sites with loads of marketing information. It can be useful to download online marketing material to accompany your purchase order rather than waiting weeks for the printed marketing material to arrive in the mail. The Web sites are listed in the contact information at the beginning of this review.
Overall, ER/1 offers a tremendous bargain for the money. If you can live within the databases that it supports, then ER/1 will probably exceed your expectations as a modeling tool. If you want a solid tool with loads of features that has stood the test of time, then go straight to Logic Works ERwin/ERX and you won't be sorry.
