Topic: Table dictionary?
Creating the tables there is a check box with the title checkbox :The table is dictionary.. can somone explain me in simply words???
1 2021-07-24 10:07:20 (edited by v_pozidis 2021-07-24 10:11:07)
Re: Table dictionary?
The table (say LU_001) that is a dictionary, is simply a look-up list linked to other tables (say AA_001) via the Relationship field. A form (say AA_Form_001) that saves data to AA_001 can have a combo box that refers to the foreign key AA-001.id_LU_001.
Re: Table dictionary?
Can not understand it. So if I have a relationship and in the form I use a combobox should I use the dictionary? Maby an example can help me ?
Re: Table dictionary?
Quite honestly I never understood it either. According to a post by Dimitry it is used in an internal algorithm in the program but it has no affect on the speed. I never check this check box and my apps work just fine. I have plenty of lookup tables without it checked.
- jean.brezhonek
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Re: Table dictionary?
Hello v_pozidis, hello ehwagner
Dictionary tables are specific to Embarcadero RAD (from which MVD is programmed (RAD XE3)).
Here is how Embarcadero describes these dictionary tables :
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.
A programming interface to the Data Dictionary is available in the drintf unit (located in the lib directory). This interface supplies the following methods:
JB
- jean.brezhonek
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Re: Table dictionary?
Me again !
That said, as ehwagner says, in my MVD applications, I have never checked the checkbox "This table is a dictionary" and that is also not a problem for me: my projects work very well in all functions and since my first (management on birds) until my last this week (management of a stamp collection).
JB
Re: Table dictionary?
I still do not understand...but I thank you for your time answering me...
8 2021-07-26 07:19:36 (edited by k245 2021-07-26 07:21:35)
- k245
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Re: Table dictionary?
Suppose you have two tables, Master and Detail, which are related in a one-to-many relationship. In this case, setting the dictionary flag on Detail table will help the internal MVD algorithm when building a query to display tabular data in which both tables participate.
But in practice, in simple cases (only two table data in view), the table is displayed correctly without setting this flag, and in complex cases (more then two tables in view) this flag does not always help. So it looks like an appendix - theoretically you need it, but you can live without it. 
Визуальное программирование: блог и телеграм-канал.
Re: Table dictionary?
I start to understand
Thank's