Xtab Users Guide

The xtab is an HTML table rendered from XML DOM data structures with a JAVAScript user interface. It is intended to be used instead of an OLAP tool loading a potentially large set of data to be manipulated locally. Speed scales linearly with the amount of data with the interface remaining responsive with thousands or rows of data. Data is generally sourced from a Web application connected to a database which generates an HTML page containing a string of XML which is used to initialise the data matrix. This string contains column elements describing each column and row elements containing the actual data.

The Xtab requires Internet Explorer V5+ with MSXML3 installed. If you experience problems with your firewall a zipped tar file version of this file is available here.

Data is represented as a tree of groupings with all numeric values totaled, integers displayed in orange, positive floating point numbers in green, negative floating point numbers in red. String values are only displayed if they are being used in a grouping or there is only one record in the group.

As successive sub groupings are added they are shown with progressively darker shades of blue until the underlying records are viewed by "opening" the group with a black background. In order to control the groupings right click on the data area of the table and select the column to group or total by.

Click here for an overview of how the XTab works.

A faster C++ ActiveX ATL implementation of grouping is available as xtab.tgz (40k). Extract this file to the directory \winnt\system32 then use the script xtab.bat to run "regsvr32 xtab.dll" in this directory to make the ActiveX "Xtab.XtabControl" available to Internet Explorer pages (subject to your security settings.)

Context Menu items (Right-Click on table):

  • "Group by" - adds a column to the current grouping.
  • "Total by" - starts another sub grouping.
  • "Open by" - start a sub grouping and opens all underlying records.
  • "Open All" - Opens the grouping/totaling node that was clicked on.
  • "Reset groups" - resets all groupings and reinitialises the node tree.

    These items are applied to the grouping node clicked on, therefore they only apply to the complete data set if the last master total row is clicked or the heading. The first item of the column sub menu is always the column that was clicked on as a convenience.

    Column operations
    The next set of menu items use the column for their context. Sorts can be applied ascending or descending and are cumulative until reset using the "reset sorts" menu item. Show and hide manage the display of hidden columns (received from the server with a "#" character at the start of their names. The layout of columns can also be changed by clicking and dragging the column header. Notice also the column header does not scroll.

    "Find" will locate all data items containing the pattern entered into the find dialog, displaying them with a gray background. "Edit" will change the value of an underlying data item locally. If the primary keys of the source table of the column being edited are present in the result set, xtab will generate and send back to the server SQL to update the value using a simple embedded JAVA applet.