It is hard to predict the needs of a particular application, so the organization of a target's libraries generally evolves over the development cycle. PowerBuilder lets you reorganize your libraries easily at any time.
For small applications, you might use only one library, but for larger applications, you should split the application into different libraries.
There are no limits to how large libraries can be, but for performance and convenience, you should follow these guidelines:
Number of objects It is a good idea not to have more than 50 or 60 objects saved in a library. This is strictly for your convenience; the number of objects does not affect performance. If you have many objects in a library, list boxes that list library objects become unmanageable and the System Tree and Library painter become more difficult to use.
Balance Managing a large number of libraries with only a few objects makes the library search path too long and can slow performance by forcing PowerBuilder to look through many libraries to find an object. Try to maintain a balance between the size and number of libraries.