Table Viewer in QlikView

This chapter describes how the QlikView Table Viewer can assist you in creating a logical, efficient data model. The QlikView Table Viewer can assist you in documenting and analyzing QlikView applications (exporting data model images and structure), finding connection issues that create synthetic keys and tables, identifying opportunities to conform to the desired star schema model, and previewing data and statistics of data inside QlikView tables.

Table Viewer in Qlikview

The QlikView Table Viewer is a graphical tool that QlikView developers use to visualize the QlikView data model (the structure, organization, and connections of data elements) of the currently open QlikView application or QVW.

When the data model is opened in Table Viewer, QlikView tables are displayed as boxes containing rows. The name of the QlikView table is displayed in the blue title box on each table, and the field names defined in the QlikView script are present in the rows.

QlikView is said to be associative, so the data fields with identical names are automatically linked together with blue connector lines. As a note, you can specifically tell QlikView to not automatically link data fields by either renaming fields as described in Chapter 4, ‘Script Features and Functions’, or using the QUALIFY statement.

The tables can be moved around the Table Viewer space (by clicking on the table header and then dragging it) and the resulting arrangement is saved when you click on OK. This does not affect the connections and data model tables. An alternate method to the developer arranging the tables, viewed in the data model layout in Table Viewer, is to select the Auto-Layout command from the menu bar.

This method leads to quirky results, so the efficient practice is to manually arrange the tables in Table Viewer (if you wish to do; many developers do not bother too much with Table Viewer organization, but you should always consult Table Viewer as a best practice to better understand the associations made by your QlikView script). Clicking on Cancel in Table Viewer will close Table Viewer without saving the new organization and views of the tables.

It can be used for many things: to get an overview, to debug what is done in the script, to check that all tables are linked, to check that you don’t have any unwanted synthetic keys, and to preview data.

Much about a QlikView application’s tables and associations can be learned by a thoughtful tour of

Table Viewer:

There are two modes of the table viewer: The Internal table view and the Source table view. The only difference between them is how the synthetic keys are displayed.

• The internal view displays a view when QlikView internally links or stores the table like if there is a synthetic key created or synthetic fields are created. We are able to see the tables and keys on the internal view. Basically synthetic table is created and it is used to link the composite multiple same keys in the different tables. The Internal Table View is the default view. It shows the data tables as QlikView stores them. Composite synthetic keys are formed in tables that share more than one field. Synthetic tables are used to link them. This view offers the best understanding of the QlikView logic and also provides a very clean layout where each pair of tables has a maximum of one connector between them.

•  The source table view is a view where if there is a synthetic table or fields is created. It will show only links.The Source Table View shows data tables as QlikView reads them. Here there are no synthetic fields or synthetic tables. Composite keys are represented by multiple connectors between tables.

• Its general functions:

• View data field and table associations by clicking on the table dialog title bar.

• View data field information for tables by moving the mouse over a table dialog title bar. Information such as table name, number of rows, fields, and keys is shown. We didn’t do this in the following example, but you can also add comments to a table tooltip by using the Comment Tables statement anywhere in the script, as shown:

          Comment table Physician Order Facts with example

• View associations (connections) between data fields in multiple tables by clicking on a data field in any table.

• Preview data (limited preview of 1000 rows) by right-clicking on a table, and then clicking on

Preview:

See the Previewing records in the tables section for more information on how to preview the table data.

• View information about each data field by hovering over any data field in a table.