Hello Graeme, if you do step1 then step2 is automatically done (no additional work for you). There is the same situation for step4 and step3 (if you connect to the database the transaction is automatically set). Step5b: You can connect the SQLQuery to a second Datasource. If you connect the components in the right order you will not get surprises.
Regards, Swen Graeme Geldenhuys schrieb: > Hi, > > Please bare with me.... Lets get one thing out of the way. I never use > DB Connection components on Forms and never use DB-aware components. > I'm a OPF guy, so using the database components on a day-to-day basis > is not something I am familiar with. > > So that said, I thought I would play with the SqlDB components today > because I want to complete the SqlDB persistence layer for tiOPF. > > The ingredients I used for today are: > TIBConnection, TSQLTransaction, TSQLQuery, TDataSource and TDBGrid. > > I got everything to work and data to be displayed in the TDBGrid, but > here is where the 'madness' part comes in. The _very strange_ way I > had to connect the above components. > > Step 1: > ====== > TIBConnection <- TSQLTransaction via 'Database' property. No problem > here. > > Step 2: > ====== > TIBConnection -> TSQLTransaction via 'Transaction' property. > Why??? Why must you link components in both directions? > > Step 3: > ====== > TSQLTransaction <- TSQLQuery via 'Transaction' property. No problems here. > > Step 4: > ====== > TIBConnection <- TSQLQuery via 'Database' property. Why??? Can't > it figure it out from the TSQLTransaction it's hooked up to already > (step 3)? What happens if the Transaction component is hooked up to > DB1 and then I specify DB2 in the Database property? > > Step 5a: > ====== > TSQLQuery <- TDatasource via the 'Dataset' property. No problems here. > > Step 5b: (optional) > ====== > TSQLQuery -> TDatasource via the 'DataSource' property. It can be > done, but wasn't needed to get my example project to work. Not sure > what's the rules about this one. > > Step 6: > ====== > TDBGrid <- TDatasource via the 'DataSource' property. No problems here. > > > > So if you haven't figured it out, my issues are with steps 2, 4 & 5b. > I really can't see why they are needed in the first place. Linking > components in both directions are simply redundant. Has nobody > thought this as strange? > > It's like dropping a PopupMenu on a Form and then setting the > following (which isn't needed by the way). Form.PopupMenu := > PopupMenu. & PopupMenu.Control := Form > > I worked with Delphi 7 using BDE and DOA (Direct Oracle Access) and > never had to set links between database components in both directions. > > > > Below is the code generated in the .lfm file if the above wasn't clear. > > -------------------[ Copy ]------------------------ > object IBConnection1: TIBConnection > Connected = True > Streamedconnected = True > DatabaseName = 'm2' > Password = 'masterkey' > Transaction = SQLTransaction1 > UserName = 'sysdba' > HostName = '192.168.0.1' > Dialect = 3 > left = 40 > top = 8 > end > object SQLTransaction1: TSQLTransaction > Active = True > Database = IBConnection1 > left = 78 > top = 8 > end > object SQLQuery1: TSQLQuery > Active = True > Database = IBConnection1 > Transaction = SQLTransaction1 > SQL.Strings = ( > 'select * from Users' > ) > Params = <> > UpdateMode = upWhereKeyOnly > UsePrimaryKeyAsKey = True > ParseSQL = True > left = 118 > top = 8 > end > object Datasource1: TDatasource > DataSet = SQLQuery1 > left = 78 > top = 48 > end > -------------------[ End ]------------------------ > > > > Regards, > - Graeme - > > > _______________________________________________ > fpGUI - a cross-platform Free Pascal GUI toolkit > http://opensoft.homeip.net/fpgui/ > > _________________________________________________________________ > To unsubscribe: mail [EMAIL PROTECTED] with > "unsubscribe" as the Subject > archives at http://www.lazarus.freepascal.org/mailarchives > > > _________________________________________________________________ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives
