firedac

问题 I am using Delphi XE5 and I have created basic Firemonkey Mobile Application - Delphi I would like to connect to a remote MySQL database. Which if any database conduit do I use? (FireDAC, DBExpress, etc)? 回答1: You can use standard TSQLQueries, but as your mobile app needs to connect to a remote database, you will need to go via a DataSnap service (most probably hosted on an IIS server). The mobile device then connects to the DataSnap server which then connects to the database. The DataSnap

问题 In replacement of my previous question which was confusing and poorly formulated, here is the "real" question. I would like to known how to set, with Firedac, at runtime, a relative path to a sqlite database located in a subfolder of my application folder. As Jerry Dodge stated : Any application should never rely on writable data in the same directory anyway. Also, even if you did, you should make sure all your paths are relative to the application at least. At the moment, the application I

问题 After attaching the second database I tried to insert and update data in the table of the first database using ON CONFLICT(id) DO UPDATE. Field id is the primary key for the first table. FDQuery1.EXECSQL('ATTACH ''D:\Update2019.DB'' AS DBUpdate'); FDQuery1.SQL.Text:= 'INSERT INTO acts (id,title) SELECT id,title FROM DBUpdate.acts'+ ' WHERE (DBUpdate.acts.id >100)'+ ' ON CONFLICT(id) DO UPDATE SET'+ ' title=excluded.title;' FDQuery1.ExecSQL; I get error message: "ERROR near "ON":syntax error"

问题 I'm using Delphi Seattle to create a brand new table in a brand new SQLite file and using only FieldDefs and non-visual code. I can create a table using the ExecSQL ('CREATE TABLE....' ) syntax but not as shown below (I get 'No such table 'MyTable' which is raised when I execute the CreateDataSet call). I'd like some solution that allows me to work with FieldDefs. This code is modelled on the example here. I notice though, that there is note regarding CreateDataSet that it only applies to

问题 I recently changed from AnyDac to FireDac (8.0.5.3365). We're running Delphi 2006. When I was using the AnyDac version of this component I could create a new database by doing the following.. Setup my connection fConnection.LoginPrompt := false; fConnection.ResourceOptions.SilentMode := true; fConnection.Params.Clear; fConnection.Params.Add(Format('DriverID=%s', ['IB'])); fConnection.Params.Add(Format('Database=%s', [fConnectionInfo.xDatabase])); fConnection.Params.Add(Format('CharacterSet=%s

问题 I am creating a temp table in SQL and then adding a new field to it. It seems Firedac is caching the field list for this temp table. The following code gives me "FDQuery5: Field 'Available' not found." FDQuery5.Connection := FDConnection1; FDConnection1.ExecSQL('Select StockNo into #Temp from Stock'); FDQuery5.SQL.Text := 'Select * From #Temp'; FDQuery5.open; FDConnection1.ExecSQL('Alter Table #Temp add Available Char(1)'); FDQuery5.Close; FDQuery5.open; ShowMessage(FDQuery5.FieldByName(

问题 My Delphi code opens a TFDQuery (FireDAC), then opens the TClientDataSet connected to it via a TDataSetProvider : ClientDataSetData.Close; with QueryData do begin Close; SQL.Clear; SQL.Add(ASelectSQL); Open; end; ClientDataSetData.Open; ASelectSQL contains this SQL: SELECT TT_NIV_ID, TT_NIV, REPLACE(TT_NIV_NAME, '|', '!') as TT_NIV_NAME2 FROM TT_SYS_PRJ_NIV The ClientDataSetData.Open gives an insufficient memory error on a dataset with 42200 records. If I inspect the result data (in the

问题 After changing to FireDAC I have trouble getting this code to work on MSSQL/Oracle: with DataFormsettings do begin Close; if Params.Count=0 then FetchParams; Params.ParamByName('TT_EMP_ID').Asinteger := AEmpID; Params.ParamByName('TT_FORM').AString := UpperCase(AKey); Open; if (RecordCount>0) then S := FieldByName('TT_VIEWDATA').Asstring; end; AKey and S are both strings. The Open statement gives an error [FireDAC][Phys][MSSQL]-338 Param type changed from [ftString] to [ftWidestring] [FireDAC

问题 Trying Delphi 10.2 Tokyo with Paradox FireDAC ODBC on Windows 10 throws error Could not open Paradox.net. This link describes the problem: https://msdn.microsoft.com/en-us/library/bb221383(v=office.12).aspx An Embarcadero FireDAC ODBC connection to Paradox table, by default will set ParadoxNetPath to System32 folder: ODBCAdvanced=CollatingSequence=ASCII;DefaultDir=C:\DEV\TPDEMOS\DATA;DriverId=538;MaxBufferSize=2048;MaxScanRows=8;PageTimeout=600;ParadoxNetPath=C:\Windows\system32

问题 I have a Delphi app that inserts some 200,000 records (about 1GB) into an SQLite database via the FireDac component TFDTable. As it inserts, I can see the application memory increasing until I get an "Out of Memory Error". I'm guessing it has something to due with cache and paging but I cant find anything that fixes it short of closing and reopening the database every 1000 records or so. Thoughts? Edited... Sorry for the thinly worded question... The code was simple so I didn't include it but