Paul, I really apreciate a lot your help. It's very important to count on experiences from other users. Now I have a lot of elements to decide what is the best option for my app.
Really thank you. Regards Alejandro ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, January 30, 2002 11:08 AM Subject: RE: MI-L Integrated Mapping Problem > Alejandro - > > Sorry but theres no simple answer - you have to decide based on the nature > of your app. If you move up to 6.5 you'll have more options anyway ... > > The system I'm doing work on uses 'server link' - we did some comparative > tests with 'register table' and in our environment 'server link' works > better - we download a subset of data within a small geographical area > because thats where the users are working. In other words, they take the > 'hit' on loadup of the map and then work locally for optimal speed. But this > then gives us data management issues when they edit and an awful lot more > code! We're using 8i native, no SW. > > With a live table, MI controls the data it retrieves from the spatial > database, with or without or SW, based on the map screen - with a linked > table you can specifically include a spatial operator (eg within 10km of the > centre of the screen) to limit downloads but then you need to rerun the > query (ie 'refresh') to move outside that area. In other words, YOU handle > data currency in your code. > > It depends on what you need to do - (you should also check that you were > correctly using the 'CACHE' options when registerig a table). > > The tradeoff is always likely to be something like this - > > 1. Live (registered) tables - no data management issues, everyone always > sees the latest state of play. Performance overheads if the user is moving > round the map a lot and/or lots of layers. > > 2. Cached (linked) tables - more rapid interaction for the user but a longer > loadup - which the user may not mind if it only happens once. More suitable > if the user is working in a defined geographical area for the duration of a > session. > > Additionally - as per earlier postings, and this applies to live or linked - > you can reduce the interaction with the server - and speed things up - by > having as much of your 'backdrop' data in native MI TAB format as possible, > ie on a file server of hard drive. If the backdrop doesn't change very often > its simple enough to manage versions and the database will go MUCH faster > with fewer spatial queries. And this is true of ANY spatial server product > from any manufacturer. > > You can FURTHER increase performance by keeping a bare minimum of attribute > data in your spatial tables and using an ID to link to a DBMS via a > non-spatial query. This is also true of any mapping app. > > HTH > > Paul Crisp > Syntegra > > Direct: 0191 461 4522 > Mobile: 0776 414 3762 > Fax: (0191) 461 1959 > > Innovation Place Metro Riverside Park > Delta Bank Road Gateshead Tyne & Wear NE11 9DJ > > > -----Original Message----- > From: MAGS-Gerencia [mailto:[EMAIL PROTECTED]] > Sent: 30 January 2002 13:48 > To: [EMAIL PROTECTED]; [EMAIL PROTECTED] > Subject: Re: MI-L Integrated Mapping Problem > > > Paul, > > I did not still us Live, because with MI-PRO and SW for SQLServer we need > MI-PRO 6.5. We are current using 6.0. > We had for a week MI-PRO 6.5 and we tested "live tables" using cache option > and I saw is slowly than creating a complete.tab. Are you agree or you were > able to make better tests ? > Another problem I had is that I don't know why allways retrieved all > records. According to the documentation should only retrieve the records > inside the Map bounds. With Oracle, is like I say ? > Are you using Oracle 8i or SW for Oracle ? > > Regards, > Alejandro > > ----- Original Message ----- > From: <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Wednesday, January 30, 2002 6:31 AM > Subject: RE: MI-L Integrated Mapping Problem > > > > In this instance - why not open the tables 'live' (using 'Register Table' > > rather than 'server link table'). Unless there are pressing needs for you > to > > have TAB files on the PC client - for instance network problems - its much > > simpler and does exactly what you are describing. > > > > I haven't used the SQL Spatial you've got but this works fine with Oracle > > and MI Pro/Int Mapping. > > > > HTH > > > > Paul Crisp > > Syntegra > > > > Direct: 0191 461 4522 > > Mobile: 0776 414 3762 > > Fax: (0191) 461 1959 > > > > Innovation Place Metro Riverside Park > > Delta Bank Road Gateshead Tyne & Wear NE11 9DJ > > > > > > -----Original Message----- > > From: Mags [mailto:[EMAIL PROTECTED]] > > Sent: 29 January 2002 19:36 > > To: [EMAIL PROTECTED]; [EMAIL PROTECTED] > > Subject: Re: MI-L Integrated Mapping Problem > > > > > > Paul and Vakili > > > > Thank you for your help. > > I am not sure this will be a recursive problem. If so, probably I will see > > both messages every loop and probably the system will crash. > > The reason I have the code in that event is because I have a table with > more > > than 800.000 points and lines, so I only refresh the objects inside the > map > > bounds. (due a perfomance problem) > > So if the user make a zoom/pan, I refresh only a set of records. The set > the > > user will see on the map. This allow us to work and edit a table with > > vitually unlimited records. (When the zoom is too big we don't make a > > refresh). > > With this in mind, is not practical to press a button each time the user > > make a pan/zoom. > > Neither to use a timer. > > May be with these aclarations you find out another way to help me > > > > Regards and thanks again > > Alejandro > > > > > > > > > Alejandro > > > > > > You have already realised this might be a problem (I think) from your PS > > but > > > what might be happening is that you get locked into a spiral by using > the > > > WindowContentsChanged callback - you do a server refresh which itself > may > > > change the contents of the window, resulting in another call etc etc. > > > > > > At the very least it might be introducing some instability - its almost > > > certainly recursing somewhere. > > > > > > Your best bet is to do a server refresh on a timer - eg every minute or > 30 > > > secs - or as an explicit statement when you commit an edit ie when you > > know > > > there has been a change, rather than in an event handler. As you say it > > > works fine off a command button. > > > > > > HTH > > > > > > Paul Crisp > > > Syntegra > > > > > > Direct: 0191 461 4522 > > > Mobile: 0776 414 3762 > > > Fax: (0191) 461 1959 > > > > > > Innovation Place Metro Riverside Park > > > Delta Bank Road Gateshead Tyne & Wear NE11 9DJ > > > > > > > > > -----Original Message----- > > > From: MAGS-Gerencia [mailto:[EMAIL PROTECTED]] > > > Sent: 29 January 2002 14:59 > > > To: MapInfo-L > > > Subject: MI-L Integrated Mapping Problem > > > > > > > > > > > > > > > Hi all, > > > > > > We have an application using Visual Basic and MapInfo Pro 6.0 = > > > (integrated mapping) > > > We have a problem that we don't really know how to solve it. > > > > > > We have code in the WindowContentsChanged Event of the Callback class. > > > The code is very simple.=20 > > > > > > Public Sub WindowContentsChanged(ByVal al_winID As Long > > > debug.print "before" > > > MI.do "Server Refresh Test_Table" > > > debug.print "after" > > > End Sub > > > > > > Each time the windows contects change, we refresh the table like you can > = > > > see in the code above. > > > All times the refresh is made and we see both debug messages ("before" = > > > and "after"), but most of the times (NOT ALLWAYS) the records does not = > > > appears and the mouse pointer remains in a clock until the user press = > > > any key or move the mouse at least just a little. !! > > > We tried doing MI.do "Set Proccesing On/Off", Visual Basic sentence = > > > DoEvents , Mi.do "Set Map Redraw On/Off", but nothnig. > > > > > > Anyone have had this problem before or knows how to solve it. > > > I will appreciate a lot any help. > > > > > > Regards > > > Alejandro > > > > > > PD: The Test_Table is a linked table to SpatialWare using SQLServer, but > = > > > I don't think this is the problem.=20 > > > If I code a command button the make the refresh, it runs propertly all = > > > times. The problem I think is because the Refresh is inside the = > > > WindowsContentsChanged Event, but I need the code there because the = > > > application each time the contents changed needs to retrieve others = > > > records. > > > > > > > > > > > > > > > > > > > > > > > > _______________________________________________________________________ > > > List hosting provided by Directions Magazine | www.directionsmag.com | > > > To unsubscribe, send e-mail to [EMAIL PROTECTED] and > > > put "unsubscribe MapInfo-L" in the message body. > > > > > > > > > ******************************************************************** > > > > > > This email may contain information which is privileged or confidential. > If > > you are not the intended recipient of this email, please notify the sender > > immediately and delete it without reading, copying, storing, forwarding or > > disclosing its contents to any other person > > > Thank you > > > > > > Check us out at http://www.syntegra.com > > > > > > ******************************************************************** > > > > > > > > > > > > _______________________________________________________________________ > > > List hosting provided by Directions Magazine | www.directionsmag.com | > > > To unsubscribe, send e-mail to [EMAIL PROTECTED] and > > > put "unsubscribe MapInfo-L" in the message body. > > > > > > > > > > > _______________________________________________________________________ > > List hosting provided by Directions Magazine | www.directionsmag.com | > > To unsubscribe, send e-mail to [EMAIL PROTECTED] and > > put "unsubscribe MapInfo-L" in the message body. > > > > > > ******************************************************************** > > > > This email may contain information which is privileged or confidential. If > you are not the intended recipient of this email, please notify the sender > immediately and delete it without reading, copying, storing, forwarding or > disclosing its contents to any other person > > Thank you > > > > Check us out at http://www.syntegra.com > > > > ******************************************************************** > > > > > > > > _______________________________________________________________________ > > List hosting provided by Directions Magazine | www.directionsmag.com | > > To unsubscribe, send e-mail to [EMAIL PROTECTED] and > > put "unsubscribe MapInfo-L" in the message body. > > > > > ******************************************************************** > > This email may contain information which is privileged or confidential. If you are not the intended recipient of this email, please notify the sender immediately and delete it without reading, copying, storing, forwarding or disclosing its contents to any other person > Thank you > > Check us out at http://www.syntegra.com > > ******************************************************************** > > > > _______________________________________________________________________ > List hosting provided by Directions Magazine | www.directionsmag.com | > To unsubscribe, send e-mail to [EMAIL PROTECTED] and > put "unsubscribe MapInfo-L" in the message body. > _______________________________________________________________________ List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, send e-mail to [EMAIL PROTECTED] and put "unsubscribe MapInfo-L" in the message body.
