WEBDEV Concepts

162 Part 5: Databases Analysis in practice 1 Overview When a project uses data files, it must be associated with an analysis. An analysis describes the structure of the data (data files, items, etc.) used in your project. There are two methods to describe an analysis: • 1st method : Creating the analysis directly (which means a Logical Data Model (LDM)). • 2nd method : Creating the Conceptual Data Model (CDM), then automatically creating the analysis from the CDM. For more details, see the online help. This chapter presents the first method. 2 Creating an LDM (Logical Data Model) In WEBDEV, the terms "LDM" and "Analysis" are interchangeably used to define the structure of the database associated with a project. 2.1 Creating an analysis (or LDM) To create a LDM : 1. Click in the quick access buttons. The creation window appears: click "Data" then "Analysis". The analysis creation wizard starts. 2. Specify the general details of the analysis: • the analysis name and directory . The analysis corresponds to a ".WDA" file. By default, this file will be created in the directory of the project analysis (<Project name>.ANA directory). This directory must be accessible in read/write mode. • the analysis description to briefly explain what the analysis is about. 3.  In the next step, select the type of database: • Database HFSQLDrive (paid turnkey solution, on a shared server). • HFSQL database in PCSCloud (paid turnkey solution, on a dedicated server). • HFSQL database (Client/Server or Classic). • Database accessible via a Native Connector. • Other types. 4.  In the next step, specify if necessary the connection information. 5. Validate the analysis creation wizard. A wizard to create the first data file appears automatically. 6. Create all the elements of the analysis (data files, items and links). 2.2 Adding a data file to an analysis The analysis defines the structure of the data files used by the project. In the analysis, a data file can be: • A new data file. • A preset data file, provided with WINDEV, WEBDEV or WINDEV Mobile. • A data file imported from an existing database (using a specific format, for example). The following paragraphs explain how to create a data file. To create a new data file : 1. On the "Analysis" tab, in the "Creation" group, click "New file". The data file creation wizard starts. 2. Select "Create a new data file description". 3. Specify: • the name of the data file . This name is the logical name of the data file. It will be used to handle the data file. • the caption of the data file that briefly describes the file subject. • the representation of a record in the data file. This representation makes the questions asked when describing the links easier to understand. This option must be preceded by an indefinite article (A or AN). • whether the data file includes an "Automatic identifier" item . The value of this item is unique for each record and is automatically calculated by WINDEV, WEBDEV or WINDEV Mobile.