File extension .ER1
Full Name | Developer | Category |
---|---|---|
AllFusion ERWin Data Format | Computer Associates | Data Files |
The ER1 file extension belongs to the ERWin Model software program and is used for entity relationship diagrams created by the software. It is a file type defined by Computer Associates, the developer of ERWin. It is an important part of data modeling. The diagrams created with ERWin represent data structure and relationships between entities in the system. These diagrams are used to analyze requirements and design databases for relational databases such as Oracle, Microsoft SQL Server, IBM DB2 and Access.
How It Works?
The ER1 file type is defined by a set of codes that describe all the elements used in the entity relationship diagram created with ERWin Model. The files contain information about entities such as tables, attributes, relationships between them and other objects. It also contains information about properties associated with each element, such as description, type, domain and constraints.
Other similar file extensions include ER2, ERX, ERF, which are used for different versions of the same type of model created with ERwin Model.
Programs for WINDOWS system
After installing the required software, the operating system will usually automatically associate an unknown file type (in this case .ER1) with the new application. If this does not happen, we can help the system a bit by selecting the software for it, which it should always use to open files with the .ER1 extension.
When choosing the software we can select the system to use this software every time.
Remember!
Using it for the first time it is good to check whether the .ER1 file opened in the application can be read by us and opens in a way that allows us to use it. If everything is in order, select this option the next time you open a file with the .ER1 extension. However, if the file has not opened correctly, we have to look for a different software, with which we can open files with the .ER1 extension. Select a different software from our list and install it on your computer. After the software is installed, repeat inspection openings of a .ER1 file. Sometimes you have to repeat the operation several times.
Other instructions
If none of the programs listed by us to work with the .ER1 file has not meet your expectations, you can try searching other websites. But remember to avoid downloading programs "that can open any file". These applications not only have very limited functionality, but may also expose you to expense tens of dollars when purchasing a license.
In the vast majority of cases you will find the program dedicated to support the .ER1 file, or any other file format. In addition, there is a chance that it will be a free program, and its functionality (concerning the .ER1 file) will be extended to the maximum.
It is also good to check
- if the .ER1 file has no errors
- or if it has been copied (or downloaded by the browser) thoroughly
Author’s guidelines
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Mr B. Adam
Author of the guidelines / Founder of FileExtension.info
New technologies enthusiast, helping to solve problems with the files.
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