Why restrict the modelling capability of CODASYL data structure sets?
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Several issues have been raised concerning changes to the capabilities of the CODASYL Data Description Language specifications for data structure sets. The paper argues against new restrictions suggested and for removal of existing restrictions. The issues are:
allow recursive set declaration
keep multiple member declaration
allow alternate owner declarations
The concept of "record-roles" is introduced to justify the need for these capabilities. The expanded capabilities described offer an alternate means of achieving the same end result without the need to introduce the "record-role" into the CODASYL Data Description Language.
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