Application Example Compound Acquisition

The point of this exercise is not to emphasize any particular importance of CAS numbers. In some applications, they may be stored simply as a string for reference, or even be of no interest at all. On the other hand, a corporate compound id number may be very important. Often corporate ids are compound strings, for example, encoding the occurrence of various salts, or the acquisition of the compound from some external source. Functions similar to those shown above would be required to implement a check constraint. 

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