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ment data in the “system table” area (see Figure 1). The system tablearea is normally where you (or your DBA) place the database schemathat defines the metadata (information about your data). This area isalso available to the PowerBuilder and PocketBuilder developmenttools along with Sybase’s InfoMaker report writer. All these Sybasedevelopment tools make use of the system table area (would youbelieve designed and available since PowerBuilder release 1.0) tostore “metadata” about your database. The first developer who connectsto a new database area using InfoMaker, PocketBuilder, orPowerBuilder with DBA privileges (i.e., “Create Table”) has the developmenttool automatically add five new tables to the system tablearea. These five tables are PBCatCol, PBCatEdt, PBCatFmt, PBCatTbl,and PBCatVld. To view these new System Tables, open the databasepainter and connect to your favorite database, then select the“Tables” item in the TreeView of the database Painter and use the“alternate” (aka politically incorrect “right-hand”) mouse button toproduce a pop-up menu. From the pop-up menu, select the “ShowSystem Tables” option. Once selected, this will force InfoMaker, PocketBuilder,or PowerBuilder to show you all the system table area –notice the PBCatxxx tables in the list.The PBCatxxx tables are where the Sybase IDE tools store extensionsto the database schema tables and columns that pertain to thedeveloper’s delivery of information to the GUI user. The DBMS doesnot care about the GUI world and, in fact, it detaches itself from it. Inthe graphic environment, however, we are concerned about propertiessuch as font, height, units of measure, formatting, and validating. ThePBCatxxx tables supply this exact information to the Sybase developmenttools. It should be noted here that this applies only to databasedesigners who use tools like PowerDesigner or System Architect andknow how to also load this GUI information into the Sybase PBCatxxxtables. Another alternative, before any development team starts itsproject work, is to have one developer take the time to use the DatabasePainter to include this extra “metadata.” Doing so can improvethe development time of a project from 3 to 15 times.Assuming that your manager is too naive or cheap to purchase adesign/modeling tool like PowerDesigner, fear not, you can still use theInfoMaker, PocketBuilder, or PowerBuilder’s DataBase painter toachieve this tremendous productivity gain; as you will see shortly, thiswill tie into the need and delivery of the “Context Sensitive” help.Loading Your MetadataTo begin loading your PBCatxxx System Tables using the InfoMaker,PocketBuilder, or PowerBuilder database painter, open the databasepainter and carefully note the “extended” properties of either a “table”or a “column” entity. For a table, the extended property categories arein the General tab’s “Comments,” all of the Data Font, Heading Fontand Label Font tab pages (see Figure 2). For the column entity, theextended properties are “Comments” in the General Tab, all of theHeaders, Display, Validation, and Edit Style tab pages (see Figure 3).Any property that you fill out in the areas listed above are automaticallysaved to the PBCatTbl system table (for a table) and the PBCatColssystem table for any column properties that are beyond the vendor’sANSI implementation.I should also take the time to mention that the database painter isincluded in the current DataWindow.NET product and will be presentin the new DataWindow.NET plug-in for Visual Studio 2005. So the tipsI am referring to in this article focus mainly on the PowerBuilder andPocketBuilder development tools but will also work for this new environmentas well. The PBCatxxx tables are always present after the firstconnection to your Oracle, Sybase, Microsoft, IBM, or other DBMS. Ifthere are security implications for creating these five new systemtables, Sybase provides DBA scripts to populate these table structuresmanually by using your favorite DBA utility.The next three PBCatxxx tables are for Edit Styles, Validation Rules,and Display Formats (see Figure 4). These extended properties can beadded to the System Table area using the “Extended Attributes” panelof the database painter. This allows the developer to input theseextended properties, which I would imagine most seasoned Power-Builder developers would recognize also appears in the DataWindowpainter. Taking the time to add this metadata in the DBMS will allowthis extra information to be available to the DataWindow painter duringthe creation of the DataWindow object. Take note of this last statementas this also applies to the Table and Column extended propertiesas well.Remember though that the PBCatxxx system tables are just standardDBMS tables that can be read by your development tool. While inthe database painter, you can locate the ISQL pane and select informationfrom any of the PBCatxxx tables. For example, in the Employeetable – if I attach a “Display Format” of '$#,##0;($#,##0)' to the Salarycolumn, then, using the following query:SELECT "pbcatfmt"."pbf_frmt","pbcatcol"."pbc_cnam","pbcatcol"."pbc_tnam"FROM "pbcatcol","pbcatfmt"WHERE ( "pbcatfmt"."pbf_name" = "pbcatcol"."pbc_mask" );FIGURE 1 | FIGURE 2FIGURE 3FIGURE 4FIGURE 5we can see if there is a correlationbetween the Display Format andany column – in particular, theSalary column. Running theabove query resulted in the followingresult set in my development environment and indicated thatthe display format I just created was indeed connected to the salarycolumn within the Employee table.Using the above information and test we can also extend thisbehavior to the “Comments” part of the PBCatCols system table. Thereason I might be interested in this would be to automate the Help filegeneration. Then I could use the ShowPopUp ( ) command in Power-Builder to dynamically support this feature. An SQL query for thisinformation might look like this:pbdj.sys-con.comPBDJ volume12 issue1117