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The Data Dictionary
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When you use the BDE to access your data, your application has access to the Data Dictionary. The Data Dictionary provides a customizable storage area, independent of your applications, where you can create extended field attribute sets that describe the content and appearance of data.

For example, if you frequently develop financial applications, you may create a number of specialized field attribute sets describing different display formats for currency. When you create datasets for your application at design time, rather than using the Object Inspector to set the currency fields in each dataset by hand, you can associate those fields with an extended field attribute set in the data dictionary. Using the data dictionary ensures a consistent data appearance within and across the applications you create.

In a client/server environment, the Data Dictionary can reside on a remote server for additional sharing of information.

To learn how to create extended field attribute sets from the Fields editor at design time, and how to associate them with fields throughout the datasets in your application, see Creating attribute sets for field components. To learn more about creating a data dictionary and extended field attributes with the SQL and Database Explorers, see their respective online help files.

Note: A programming interface to the Data Dictionary is available in the drintf unit (located in the lib directory). This interface supplies the following methods:

Data Dictionary interface

Routine | Use
DictionaryActive | Indicates if the data dictionary is active.
DictionaryDeactivate | Deactivates the data dictionary.
IsNullID | Indicates whether a given ID is a null ID
FindDatabaseID | Returns the ID for a database given its alias.
FindTableID | Returns the ID for a table in a specified database.
FindFieldID | Returns the ID for a field in a specified table.
FindAttrID | Returns the ID for a named attribute set.
GetAttrName | Returns the name an attribute set given its ID.
GetAttrNames | Executes a callback for each attribute set in the dictionary.
GetAttrID | Returns the ID of the attribute set for a specified field.
NewAttr | Creates a new attribute set from a field component.
UpdateAttr | Updates an attribute set to match the properties of a field.
CreateField | Creates a field component based on stored attributes.
UpdateField | Changes the properties of a field to match a specified attribute set.
AssociateAttr | Associates an attribute set with a given field ID.
UnassociateAttr | Removes an attribute set association for a field ID.
GetControlClass | Returns the control class for a specified attribute ID.
QualifyTableName | Returns a fully qualified table name (qualified by user name).
QualifyTableNameByName | Returns a fully qualified table name (qualified by user name).
HasConstraints | Indicates whether the dataset has constraints in the dictionary.
UpdateConstraints | Updates the imported constraints of a dataset.
UpdateDataset | Updates a dataset to the current settings and constraints in the dictionary.

See Also

BDE-based Architecture

Tools for Working with the BDE

Using Transactions with the BDE

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