CHT Changes Posted To WEBUPDATER June 27, 2008

We posted some changes to CHT WEBUPDATER June 27, 2008. This was not done as a version change for the time being, as the basic CHT classes and templates have not changed from the 12B1.01 which you've had since May 22, 2008.

At least until the end of July 2008, which is our target date for the release of build 12C1.00, there are going to be fairly frequent periodic updates without version number changes in order to introduce some new templates into the system so that an SQL project I'm working on can make use of them. You can feel comfortable downloading this un-reversioned update since it does not affect existing templates and classes that you've already been using. And it will give you a chance, if you're interested, in getting a preliminary look at some new templates,many of which are going to be targeted at SQL.

In this upload is a new template called ExplorerBrowseLocatorEx. This is an expanded version of ExplorerBrowseLocator (hence the "EX" suffix) that adds some features:

•  A "Go" button beside the locator to execute the locator. (Tab still works as before).

•  An automatic pass-through of the browse's "Data With Query Only" feature when the locator is set up as a filtering locator. This does work in the previous locator, but not if you've embedded your own filter into the browse. This new control lets you embed your own filter in the browse's ApplyFilter method, and still enforce "Data With Query Only" so that nothing displays unless the locator has been used.

•  There is a more sophisticated algorithm for "Drill-Down" in this locator, including a "bread-crumbs" string control that displays the current query, either as SQL or as CHT Query language. This works like "QBE", or "Query By Example" if you set the locator for "Drill-Down" since you can filter on multiple columns one after the other just by clicking on them and entering a new value in the locator. The new query is ANDed to the previous one until you click the Clear button.

Also coming for this new locator - when in filtering mode - is the ability to define on a column-by-column basis what the query keyword is for that column. So, a date or numeric column can use EQUAL while a text column can use CONTAINS.

There will be an equivalent locator for HandyMarkerBrowse early in July.

We're also working on a new SQL trace feature for CHT browses using HNDSQLTRACE.APP. This isn't available yet in the June 27th posting. The next HNDSQLTRACE.APP will have a filter feature that lets you trace a particular table or exclude a particular table. You'll also be able to direct output from our other SQL trace features, for example HandyQueryTracingButton_EXPB into HNDSQLTRACE.APP and a new option on that template lets you opt to see the entire SQL select including WHERE and ORDER BY.

More SQL-related features coming. I'll tell you about those as they are introduced and uploaded for you to try. We're about ready to release an "Experimental" switch on all CHT browse extension templates. This feature optimizes your CHT-extended ABC browse for SQL by overriding some of the ABC browse features that were really intended for ISAM tables and get in the way of SQL.

We're calling this "Experimental" because it's not default behavior, you have to turn this setting on to invoke the features set. We're going to let you try this feature on your browses for a while by way of an "experiment". Primarily it reduces the amount of SQL "chatter" that ABC browses - especially page loaded browses - tend to produce and slows them down. We'll be looking for your feedback on the impact of this on your SQL browses and, of course, we're prepared to take your questions and suggestions for improvements.

Cheers...
Gus M. Creces
The Clarion Handy Tools Page
http://www.cwhandy.ca