New Program Update Sept 12, 2012 Build 187

Transcription

1 New Program Update Sept 12, 2012 Build 187 What s Inside Main Module Improved Handling of Calc Races Database Locked Condition Background Info - Why does the database locked condition occur? From what I can see on the machines I am using, and from what I have been able to determine by reading about how Windows handles multiple apps running at the same time: Whenever a machine runs low on memory it halts execution of apps running in open program windows. (This includes apps running in the background not launched by the user - or even without the user being aware they are running.) Once everything has been halted, Windows then writes everything in memory to the swap or paging file, clears everything in memory, and then reloads everything in the swap or paging file back into memory - and only then - begins running apps again. This process can take several minutes. And depending on what is running in the background and how much memory the apps running are (collectively) using can sometimes cause a machine to wind up in a state where the machine is constantly halting program execution so that the machine can continually go through the exercise of writing to and reading from the swap file. During a Calc Races routine, logic in the Calc Races routine itself performs hundreds of read/write operations to the tables in the c:\jcapper\exe\jcapper2.mdb file. Windows has a mechanism for securing.mdb database files. When a program is actively engaged in the act of reading data from or writing data to an.mdb database file, Windows locks the file so that other apps (and/or users) can t write to that file while it s in use. The mechanism for doing this is to put a lock file on the same folder as the.mdb file. Lock files have the same file name as the.mdb file except for the file extension. The file extension for a lock file are the characters.ldb (without the quotes.) If you were to sit and watch the c:\jcapper\exe folder during a SQL Calc Races, you would see a file named JCapper2.ldb (that s the lock file) placed on the folder whenever the Main Module is reading from or writing to the JCapper2.mdb file. You would also see the JCapper2.ldb lock file cleared (deleted) from the folder each time the Main Module isn t actively engaged in reading data from or writing to the JCapper2.mdb file.

2 The database locked condition comes into play when a machine runs out of memory during a Calc Races and has to start writing to the swap file. Under those circumstances, Windows is slow to clear the lock file. When the JCapper Main Module attempts to read from or write to its own database file but can t because Windows hasn t been able to clear the lock file from the folder a database locked error message is the result. Database Locked Handling Description (Old Way) Up until now, the way that I have handled a database locked error inside of the JCapper Main Module was to present the user with a message box displaying a database locked message while at the same time offering the user an auto recovery option that when clicked allows the Calc Races routine to be run to completion. What you may not have known is what goes on behind the scenes (on your machine) when that database locked message appears. I created that database locked message box in such a way that the Calc Races routine itself has to stop executing while the message is displayed. This gives Windows the time it needs to catch up and clear the lock file. By the time you click the message and select the auto recovery path, the lock file has long been deleted from the folder enabling the.mdb file to be read from and written to again. That strategy might be clumsy and inelegant. But it works. Improved Handling of Calc Races Database Locked Condition The Main Module in this program update comes with a new (better) way of handling the database locked condition. Database Locked Handling Description (New Way) During a Calc Races routine, the JCapper Main Module in this program update handles the presence of an.ldb lock file on the JCapper2.mdb file in the following manner: 1. The Calc Races routine is halted for a few seconds. The folder where the Calc Races is being run is tested for the presence of the lock file. In most cases (on most machines) halting the routine for a few seconds will give Windows the chance to catch up and clear the lock file. If testing reveals that the lock has been cleared, program execution of the Calc Races picks up where it left off without the user ever being made aware (via a database locked message) that a database locked condition was encountered. 2. If testing reveals that the lock file is still there, the Calc Races routine is halted for another 2-3 seconds giving Windows a second chance to catch up. The folder where the Calc Races is being run is once again tested for the presence of a lock file. In almost all cases (on most machines) halting the routine a second time for a few seconds gives Windows the time it needs to catch up and clear the lock file. The folder is retested, and if testing reveals that the lock has (finally) been cleared, program execution of the Calc Races picks up where it left off again without the user ever being made aware (with a database locked message) that a database locked condition was encountered.

3 3. However, if at this point testing reveals that the lock file is still there, the assumption is made that Windows needs more than just a second or two and a database locked message is generated and you will have to click through it and select the auto recovery path to restart the Calc Races so that it can be run all the way to completion. --end Main Module section-- Scratch Parser The JCapper Scratch Parser in this program update has been reprogrammed so that it can (once again) parse scratches from the (recently) revised scratches pages at the Brisnet site. The JCapper Scratch Parser in this program update also enables you to parse the scratches and race changes web pages maintained by HDW (Handicapper s Data Warehouse.) Brisnet Scratches Brisnet maintains an index of scratches pages for individual race tracks (one web page for each race card) at the following url: Viewing the web pages is free but a valid Brisnet username and password is required. Scratch Parser vs. Scratch BOT In mid July, 2012 I had several phone conversations with upper management at Brisnet. At the time, Brisnet had just gone to a new database and the reason I called them was twofold. First, a number of you were reporting problems with Brisnet.DRF Single and.mcp Multicaps comma delimited text data files. Second, Brisnet had also made formatting changes to the html for the scratches web pages on their site. In so doing they had managed to break apps horseplayers were using (such as the original JCapper Scratch Parser) to parse scratches from those web pages. I was told that Brisnet was now using the Equibase Scratches and Changes XML as the primary data source for the scratches compiled at Brisnet.com. I mention this to make you aware that JCapper Scratch BOT enables you to parse the XML directly giving you an advantage in timeliness/accuracy over using the Scratch Parser to parse scratches from Brisnet.com.

4 Consider: 1. When you use Scratch BOT to parse the XML directly you are getting scratches as they exist at the point in time when you click the XML button. (This is as close to real time as possible.) 2. When you use the Scratch Parser to parse scratches from the web pages on the Brisnet site, you are getting scratches as they existed at the point in time that the last XML parse routine was executed by the Brisnet server. (The possibility for lag time is very real.) Scratch BOT is the superior tool when it comes to parsing scratches and changes from the internet. Even so, and even though Scratch BOT is the tool that I use myself for parsing scratches and changes from the internet - the JCapper Scratch Parser does offer one advantage: Simplicity. Unlike Scratch BOT, which requires that you maintain a set of table entries for each track you want to parse from the xml - the Scratch Parser has no such requirement. With the Scratch Parser, you simply point, click, pull up a web page with scratches on it and hit the PARSE button to get scratches as compiled by data vendors Brisnet and HDW. BASIC OPERATING INSTRUCTIONS for Using the JCapper Scratch Parser to Parse Scratches from the Brisnet Site: 1. Select the Brisnet option from the Address Bar (located in the upper left screen area of the module.) When you select the Brisnet option, the interface will populate the address bar with the url to the scratches index at Brisnet.com. 2. Click the url on the Brisnet site for an individual race card. Note that viewing the scratches page for an individual race card requires a login using a valid Brisnet username and password. After logging in, the Scratches Parser module behaves as a web browser and will render the scratches page for the requested race card so that you can both read it and parse it. 3. After the scratches page for the requested race card has been rendered, click the PARSE button. This will cause the interface to parse the scratches web page for new scratches. The interface will compare the scratched horses listed in the html for the page being parsed against the scratched horses in the scratches.txt file on the folder where you have that race card loaded. Any new scratches found are written to the scratches.txt file on the folder where that race card was loaded. After the html for the requested page has been parsed and new scratches have been written to the scratches.txt file, you will get a message box that gives you a

5 list of the new scratches. That message box will also remind you that before you can see the effect of the new scratches on your html report you will need to run a Calc Races and refresh the Report Viewer. 4. Click the HOME button to return to the Brisnet index page. Then, repeat steps 2 and 3 above until parse routines have been run for each track you have loaded into JCapper. Note: When you parse scratches from the Brisnet site, you are parsing a web page listing all known scratches for one race card only. (The default url when you select the Brisnet option from the address bar takes you to an index of scratches web pages for individual race cards.) From there, you have to parse scratches for the individual race cards that you want. Note: Brisnet auto updates the scratches web pages on their site regular intervals throughout the race day. When you parse the daily scratches web pages on the Brisnet site you are getting scratches as of the most recent XML parse routine executed on the Brisnet server. This may work for most of you. It may not be acceptable for all of you as there may be scratches out there not yet available on the Brisnet site. IMPORTANT: If you want the most current scratches and changes available (in as close to real time as possible) I strongly suggest that you parse the XML directly using Scratch BOT. Note: Brisnet normally leaves the scratches web pages for each race card up on their site for approximately 7-8 days. This makes a reasonably good source when you want scratches info for recent prior race cards. Brisnet does run a routine on their server that takes the pages for older race cards down automatically. Unless that routine fails, expect the links to race cards older than 8 days to disappear from the rotation. Note: You can use the Card Loader in the DFM (as well as the original Card Loaders and the Card Loader on Screen Two of the Brisnet File Downloader) to load race cards for prior race dates into JCapper. From there, clicking the link to the scratches page for a prior race card followed by clicking the PARSE SCRATCHES button will enable you to parse in scratches for any race card loaded into JCapper for the prior race date. HDW Scratches The JCapper Scratch Parser in this program update now enables JCapper customers to parse the scratches pages maintained by HDW on the HDW site. Viewing and parsing the scratches pages on the HDW site is free but does require a valid HDW username and password. (You will have to log into the HDW site when parsing HDW scratches pages using the JCapper Scratch Parser.)

6 Scratch Parser vs. Scratch BOT In mid August, 2012 while reworking the JCapper Scratches Parser to handle the recently reformatted Brisnet scratches html, I asked Ron Tiller at HDW about JCapper customers getting access to the same scratches and changes web pages that HDW produces for HTR and HSH. Ron was only too happy to comply. A few things to keep in mind about the scratches pages on the HDW site: Just like Brisnet, HDW is now parsing the Equibase Scratches and Changes XML and using it as the primary data source for scratches reported on their site. I mention this to make you aware that JCapper Scratch BOT enables you to parse the XML directly giving you an advantage in timeliness/accuracy over using the Scratch Parser to parse scratches from either the Brisnet or HDW sites. Consider: 1. When you use Scratch BOT to parse the XML directly you are getting scratches as they exist at the point in time when you click the XML button. (This is as close to real time as possible.) 2. When you use the Scratch Parser to parse scratches from the web pages on the HDW site, you are getting scratches as they existed at the point in time that the last XML parse routine was executed by the HDW server. (The possibility for lag time is very real.) Scratch BOT is the superior tool when it comes to parsing scratches and changes from the internet. Even so, and even though Scratch BOT is the tool that I use myself for parsing scratches and changes from the internet - the JCapper Scratch Parser does offer one advantage: Simplicity. Unlike Scratch BOT, which requires that you maintain a set of table entries for each track you want to parse from the xml - the Scratch Parser has no such requirement. With the Scratch Parser, you simply point, click, pull up a web page with scratches on it and hit the PARSE button to get scratches as compiled by data vendors Brisnet and HDW. BASIC OPERATING INSTRUCTIONS for Using the JCapper Scratch Parser to Parse Scratches from the HDW Site: 1. Select the HDW Scratches option from the Address Bar (located in the upper left screen area of the module.) When you select the HDW Scratches option, the interface will populate the address bar with the url to the scratches page at the HDW site for today s race date.

7 2. After the scratches page for the requested race date has been rendered, click the PARSE button. This will cause the interface to parse the scratches web page for new scratches. The interface will compare the scratched horses listed in the html for the page being parsed against the scratched horses in the scratches.txt file on the folder where you have each race card loaded. Any new scratches found are written to the scratches.txt file on the folder where a given race card is loaded. After the html for the requested page has been parsed and new scratches have been written to the scratches.txt file, you will get a message box that gives you a hard count of new scratches found. That message box will also remind you that before you can see the effect of the new scratches on your html report you will need to run a Calc Races and refresh the Report Viewer. Note: When you parse scratches from the HDW site, you are parsing a web page listing all scratches for an individual race date. (The default url when you select the HDW option from the address bar takes you to the scratches web page for today s race date.) Note: HDW auto updates the scratches web page on their site for each race date at (roughly) minute intervals throughout the race day. When you parse the daily scratches web page you are getting scratches as of the most recent XML parse routine executed by the HDW server. This may work for most of you. It may not be acceptable for all of you as there may be scratches out there not yet available on the HDW site. IMPORTANT: If you want the most current scratches and changes available (in as close to real time as possible) I strongly suggest that you parse the XML directly using Scratch BOT. Scratches Pages for Prior Race Days Note: HDW normally leaves the scratches web pages for each race day up on their site for at least 45 days. This makes a better source than Brisnet when you want scratches info for prior race dates. Ron or someone else at HDW has to take the pages down manually when it s time to remove them (so there s a good chance they may be left up a lot longer than the 45 days promised.) Note: Take a look at the date embedded into the default url in the address bar when you click the HDW option. By manually editing the date embedded in the url to a date for a known prior race day, and editing the text in the address bar so that the remaining text is a pure url beginning with the characters http (without the quotes) - clicking the GO button will cause the JCapper Scratch Parser to navigate to the url in the address bar and render a scratches page for the requested prior race day. (And that s how you would get scratches for a prior race day if you want them.) From there, clicking the PARSE button will parse in scratches for any race cards loaded into JCapper for the prior race date. IMPORTANT: The GO button enables you to operate the JCapper Scratch Parser as if it were a web browser. I STRONGLY RECOMMEND THAT YOU REFRAIN FROM DOING THIS. The ONLY sites you should use the Scratches Parser to view are the

8 scratches and changes pages at either BRISNET.COM or HORSEDATA.COM. The reason for this should be apparent to you. There is no shortage of unscrupulous site operators out there. The Scratches Parser is based on Internet Explorer 7 dlls However, the Scratch Parser app is not updated with the latest security patches published by Microsoft and is in no way shape or form intended to be used as if it were a secure web browser. BASIC OPERATING INSTRUCTIONS for Using the JCapper Scratch Parser to Parse Surface Distance Changes from the HDW Site: 1. Select the HDW Surf-Dist option from the Address Bar (located in the upper left screen area of the module.) When you select the HDW Surf-Dist option, the interface will populate the address bar with the url to the race changes page at the HDW site for today s race date. 2. After the race changes page at the HDW site for the requested race date has been rendered, click the PARSE button. This will cause the interface to parse the list of race changes for surface-distance changes. The interface will compare the changes listed in the html for the page being parsed against the reaceheaders.txt file for each of the 3 active data folders as you have them persisted in the DFM (Data Folder Manager.) Any surface or distance changes for the races in card files that you have loaded into the program will be written to the raceheaders.txt file on the folder where that race card was loaded. After the html for the requested page has been parsed and surface distance changes have been written to the raceheaders.txt file, you will get a message box giving you a hard count of the changes parsed from the web page. Note that the web page itself is readable by the human eye. Also note that the message box also serves as a reminder you that before you can see the effect of race changes parsed on your html report you will need to run a Calc Races and refresh the Report Viewer. Note: HDW treats the race changes pages at their site just like the scratches pages. Both are auto updated throughout the race day at (roughly) minute intervals. Both will get you changes as of the most recent XML parse routine executed by the HDW server. This may work for most of you. It may not be acceptable for all of you as there may be changes out there in the XML that are not yet available on the HDW site. IMPORTANT: If you want the most current scratches and changes available (in as close to real time as possible) I strongly suggest that you parse the XML directly using Scratch BOT. Surface Distance Changes Pages for Prior Race Days

9 Note: HDW normally leaves the race changes web pages for each race day up on their site for at least 45 days. This makes a better source than Brisnet when you want info for prior race dates. Ron or someone else at HDW has to take the pages down manually when it s time to remove them (so there s a good chance they may be left up a lot longer than the 45 days promised.) Note: Take a look at the date embedded into the default url in the address bar when you click the HDW option. By manually editing the date embedded in the url to a date for a known prior race day, and editing the text in the address bar so that the remaining text is a pure url beginning with the characters http (without the quotes) - clicking the GO button will cause the JCapper Scratch Parser to navigate to the url in the address bar and render a scratches page for the requested prior race day. (And that s how you would get scratches for a prior race day if you want them.) From there, clicking the PARSE button will parse in scratches for any race cards loaded into JCapper for the prior race date. IMPORTANT: The GO button enables you to operate the JCapper Scratch Parser as if it were a web browser. I STRONGLY RECOMMEND THAT YOU REFRAIN FROM DOING THIS. The ONLY sites you should use the Scratches Parser to view are the scratches and changes pages at either BRISNET.COM or HORSEDATA.COM. The reason for this should be apparent to you. There is no shortage of unscrupulous site operators out there. The Scratches Parser is based on Internet Explorer 7 dlls However, the Scratch Parser app is not updated with the latest security patches published by Microsoft and is in no way shape or form intended to be used as if it were a secure web browser. Clearing Scratches The Clear Scratches button for the Scratch Parser in this program update renders as three separate buttons when you hover your mouse cursor over it. The individual Clear Scratches buttons are labeled Folder1, Folder2, and Folder3. As you might well guess, these buttons correspond to the active data folders as you have them persisted in the DFM (Data Folder Manager.) Clearing scratches is easy. To clear the scratches.txt file on the folder persisted as Folder1 in the DFM, click the Clear Scratches button for Folder1. To clear the scratches.txt file on the folder persisted as Folder2 in the DFM, click the Clear Scratches button for Folder2. To clear the scratches.txt file on the folder persisted as Folder3 in the DFM, click the Clear Scratches button for Folder3. As mentioned in the Scratch Parser Help Doc for the original JCapper Scratch Parser - it is recommended as a best practice that you clear scratches for each of your data folders at the start of each race day. Doing so will prevent the scratches.txt file from becoming corrupted and will create a brand new file in the event the file itself does become corrupted. Note that if you believe yourself to be parsing scratches properly and you find that scratched horses are still showing up on your reports the very first thing you should suspect is a corrupted scratches.txt file and the very first thing you should do in the way of corrective action is to clear the scratches.txt file. As mentioned in the help doc for the original Scratch Parser, in 99.9% of all cases that I have looked at where a user has

10 reported problems with scratched horses appearing on reports clearing the scratches.txt file took care of the problem. --end Scratch Parser section-- FAQs: Q. Do I need to check the box on the Installer to make it give me a new JCapper2.mdb file? A. Yes. This new program update contains new JCapper2.mdb table content - which requires that you make the Installer give you a new JCapper2.mdb file by checking the Overwrite JCapper2.mdg file box on the face of the Installer. Q. After checking the box to make the Installer give me a new JCapper2.mdb file, do I need to use the JCapper2 Import Module found on the User System Definitions Screen to import data from my old JCapper2.mdb file into the fresh blank JCapper2.mdb file copied onto my c:\jcapper\exe folder by the Installer? A. Yes, any time you make the installer give you a new JCapper2.mdb file, this is critical - an absolutely must - especially if you have a custom sql factor setup or a custom sql html report. Q. How do I run a JCapper2 Import routine? A. Link to video: Note: I generally recommend checking the Overwrite JCapper2.mdb File box on the face of the Installer as a best practice each time you install a new program update. I also recommend importing data out of you old JCapper2.mdb file into your new file too. If you get in the habit of doing this with each new program update, you're never left guessing whether or not the new program update you just installed contains new required

11 table content. Checking the box makes the Installer give you new table content whenever it's there. Q. Do I need to rebuild databases from scratch after installing this program update? A. No. Not if you've kept current with the downloads. Now if you haven't kept current with the downloads then yes, chances are you will have to rebuild databases from scratch before using the Data Window to query playlist files built using older program versions. Q. I ve been using the same (older) program version for quite some time and haven t kept current with the downloads. Do I download and install each of the new program updates that I missed? Or does downloading and installing the latest new program update bring me current again? A. The new program updates are written in such a way that getting the latest one brings you current meaning that you can skip the ones you missed and just install the latest one. Afterwards, you will be current again. Enjoy, -jp.