DataDictionary: Difference between revisions
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= Definition = | |||
A data dictionary is defined as the business layer in-bewteen your table on disk, and the requested operation at runtime. It handles the find, clear, save, validate, and delete requests from either the programmer or the user. A data dictionary exists both as a class coded definition and as an instantiated object which uses full delegation and polymorphism in the form of a data dictionary object in a "tree" structure for the data set you wish to perform an operation on. | |||
= editing a Data Dictionary = | |||
Editing a DataDictionary CLASS in Visual DataFlex involves at least 10 identifiable options: | Editing a DataDictionary CLASS in Visual DataFlex involves at least 10 identifiable options: | ||
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All together, these 10 functional abilities to centrally define data table rules are dwarfed by the fact that they are "hitched up in tandem" like a team of "Budweiser Clydesdales" which work interconnectedly to enforce your entire data structure on any data operation which includes save, clear, find, delete, and validation. | All together, these 10 functional abilities to centrally define data table rules are dwarfed by the fact that they are "hitched up in tandem" like a team of "Budweiser Clydesdales" which work interconnectedly to enforce your entire data structure on any data operation which includes save, clear, find, delete, and validation. | ||
= | = How to use Data Dictionaries = | ||
The [[Database Builder]] tool helps you defining the class with visual aid for: | The [[Database Builder]] tool helps you defining the class with visual aid for: | ||
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The Datadictionary class can also contain and business rules required when records are created, edited or deleted. | The Datadictionary class can also contain and business rules required when records are created, edited or deleted. | ||
==How to create a new Data Dictionary from scratch== | ==How to create a new Data Dictionary from scratch== | ||
#Open [[Database Builder]]. | #Open [[Database Builder]]. | ||
#Create a new table | #Create a new table | ||
#Enter some columns (input name, type and width) | #Enter some columns (input name, type and width) | ||
#Choose '''Maintenance''' and '''Create Empty DataDictionary'''. | #Choose '''Maintenance''' and '''Create Empty DataDictionary'''. | ||
==How to create Relationships== | ==How to create Relationships== | ||
Before creating relationships, make sure that both tables should have an index. | Before creating relationships, make sure that both tables should have an index. | ||
*use 'the relationship wizard' in the database builder. | *use 'the relationship wizard' in the database builder. | ||
