DB List - classifier and DB lookup combobox - classifier

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At development of the application for operations with the database a necessity often arise for linking of two data sets by a key field. For example, a field Code1 which contains the identification code of semantics is present in the "List of semantics codes" database table. The semantics name (Name field) and its code (Code 2 field) are stored in the table "List of semantics name" under the same code. At development of user interface it is necessary to provide displaying of its name (not the code) at review of semantics in the application's form.

 Thus the semantics name field from "List of semantics name" table should appear in a data set "List of semantics codes " instead of a code field. The mechanism of fields link from different data sets by a key field is named as synchronic review. In the reviewed example the key Code 2 from the table "List of semantics name" is the key field, and the choice of the concrete name is made on coincidence of values of a key field (Code 2) and substituted field (Code 1) from the initial data set. And it is necessary that the field Code 2 in the table "List of semantics name" was unique (would be a primary key).

 The table having the field which values are substituted onto the synchronic one, we shall name as the initial table (it is the table "List of semantics names").

Let's name the table inclusive a key field and data field for synchronic review as the table of synchronic review (table the List of titles семантик).

ici_9128 DB List - classifier, ici_9129 DB lookup combobox - classifier are the components of synchronic data review.

DB List - classifier represents the list of field's values of synchronic review. Its main role is in automatical installing of correspondence between fields of two data sets by identical value of the selected field of the initial table and key field of the table of synchronic review.

By the functional capabilities the component coincides with DB List component.

By the functional capabilities the DB lookup combobox - classifier component coincides with DB Lookup combobox component.

Properties of DB List - classifier component are the followings: Color, Data field name, Dataset name,Font, Height, Hint,  Key field name, _ List field name, _ List source name, Left, Name, Show hint, Top, Width, Align.

Properties of DB lookup combobox - classifier component are the followings: Color, Data field name, Dataset name, Font, Height, Hint, Key field name, _ List field name, _ List source name, Left, Name, Show hint, Top, Width.

Data field name defines the reference onto a concrete field in the table, the values of which are substituted onto synchronic one (it is a field Code 1 in the example).

Dataset name is defined the reference onto Table component name, which is linked to the initial table (table "List of semantics codes").

Key field name - key field of the table of synchronic review (field Code  2).

_ List field name defines the reference onto a concrete field in the table for synchronic review (Name field).

_ List source name is defined the reference onto Table component name, which is linked to the table of synchronic review (table "List of semantics names").