I have added new TClientDataset in my project, to client. Also I have an Oracle stored procedure that takes clientid as input & returns cursor.
The code below executes on button click
with dmMain.cdsGetV do //cdsGetV is name of Clientdataset
begin
if Active then Close;
Params.Clear;
FetchParams;
Params.ParamByName('PCLIENTID').AsString := '0022995544';
Open;
end;
On click I have error: `
cdsGetV: parameter 'pclientid' not found.
There are many other clientdatasets like this and they work good. I copied exactly the same code of those cds', but it's still not working. Any idea what's problem?
I recreated the clientdataset and datasetprovider on server ,and now it works.
Related
Hello fellow StackOverflowers,
Currently I'm facing a situation where it seems that there is a maximum length for the Database property of a TSQLConnection object in Delphi.
When I open the connection to my database I get the following error when I use a rather long (154 chars) database name:
dbExpress Error: [0x0015]: Connection failed
SQL Server Error: unrecognized database parameter block
wrong version of database parameter block
When I relocate my database file to another location (and with that reduce the length of the path) it will connect to the database.
I am currently using the Object Inspector to set the connection properties of the TSQLConnection object.
Basically, my question comes down to this:
Does a TSQLConnection have a maximum length for the values set in the Params property? And if so, what is the maximum length of these values?
Update
I've found two ways to open a copy of Employee.Gdb in a folder with a 160-character name ('abcdefghij0123456789' x 8).
What I did firstly was to edit the DBXConnections.Ini file and changed the Database parameter in the [IBConnection] section to read
Database=localhost:D:\abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890\employee.gdb
Then, I can successfully connect to it, open the Employee.Gdb and make changes to the Customer table. I have verified the changes in IBConsole just in case the copy of Employee.Gdb wasn't the one I assumed it was.
Subsequently, I've found that I can create and open the db in code using Delphi Seattle and Interbase XE7, as follows:
function LongPath : String;
begin
Result := 'D:\' + DupeString('abcdefghij0123456789', 8);
end;
function LongDBName : String;
begin
Result := LongPath + '\Employee.Gdb';
end;
procedure TForm1.OpenDB;
var
Ini : TMemIniFile;
const
scDBXConIni = 'C:\Users\Public\Documents\Embarcadero\Studio\dbExpress\17.0\dbxconnections.ini';
scSourceDB = 'D:\Delphi\Databases\Interbase\Employee.Gdb';
begin
Ini := TMemIniFile.Create(scDBXConIni);
try
// First, blank out the Database value in the IBConnection section
// of DBXConnections.Ini
Ini.WriteString('IBConnection', 'Database', '');
Ini.UpdateFile;
// Next, create the long-named directory and copy Employee.Gdb to it
if not DirectoryExists(LongPath) then
MkDir(LongPath);
Assert(CopyFile(PChar(scSourceDB), PChar(LongDBName), False));
// Set LoadParamsOnConnect to False so that the SqlConnection uses
// the value of the Database we are about to give it
SqlConnection1.LoadParamsOnConnect := False;
SqlConnection1.Params.Values['Database'] := LongDBName;
SqlConnection1.Connected := True;
// Open the CDS to view the data
CDS1.Open;
finally
Ini.Free;
end;
end;
The critical step in doing it this way is setting LoadParamsOnConnect to False, which I confess I'd overlooked in earlier attempts to get this code to work.
I've got some earlier versions of Delphi on this machine, so if you're not using Seattle and the above code doesn't work for you, tell me which one you are using and I'll see if I can try that.
**[Original answer]
Actually, I think that this may be an error occurring in one of the DBX DLLs.
I created a folder with a 160-character name, then copied the demo Employee.Gdb database into it. Interbase XE7's IBConsole can open the db without error. So could a small test project contructed with IBX components in Delphi Seattle.
However, with an equivalent DBX project, when I use the code below
procedure TForm1.Button1Click(Sender: TObject);
begin
SqlConnection1.Params.Values['database'] := 'D:\abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890abcdefghij01234567890\employee.gdb';
SqlConnection1.Connected := True;
end;
I get an error in
procedure TDBXDynalinkConnection.DerivedOpen;
var
Count: TInt32;
Names: TWideStringArray;
Values: TWideStringArray;
IsolationLevel: Longint;
DBXError: TDBXErrorCode;
begin
Count := FConnectionProperties.Properties.Count;
FConnectionProperties.GetLists(Names, Values);
CheckResult(FMethodTable.FDBXConnection_Connect(FConnectionHandle, Count, Names, Values));
DBXError := FMethodTable.FDBXConnection_GetIsolation(FConnectionHandle, IsolationLevel);
'I/O error for file "database.gdb"
Error while trying to open file
The operation completed successfully'
and the Database param of the SqlConnection is left at the value 'Database.Gdb', which is not the value I specified, of course, nor was it the value specified in the params in the IDE, which was 'd:\delphi\databases\interbase\employee.gdb'.
I wondered if I could work around this problem by SUBSTing a drive to the 'abcdefg ...' path. I tried that and opening the database as "x:\employee.gdb" , but I get the same error in my DBX app, and also IBConsole cannot access the db either.
I think you need a shorter physical path!**
This is related to MSSql Server:
As a general guideline, long path names greater than 160 characters
might cause problems.
from Microsoft TechNet - https://technet.microsoft.com/en-us/library/ms165768(v=sql.105).aspx
I am currently trying to connect to a database using an ODBC Alias to SQL Server. The problem I'm having is that when I use my TQuery object to get the information it always requests login details (nevermind whether I've specified them in the ODBC creation). I don't mind manually setting them in the code, but I can't find how to do that.
The most common solution I've found is to use the database component and go through that. However that comes with its own issues. Due to my dataset being so large and the database component converting the dataset to a Paradox table I keep getting a BDE error of 'Temporary Table Resource Limit'.
I don't get this error if I ignore the database component (which is fine) however this leaves me with the login prompt issue. Has anyone found a way to bypass this for TQuerys without swapping to other connection paths such as ADO?
I'm a bit rusty with the BDE but I don't think there's an easy way to avoid the login prompt if what you're saying is that you're not using a TDatabase component in your project.
The reason is that when you attempt to open your TQuery without a TDatabase (or TSession) component in your project, the default Session object in your app will call the routine below from within your TQuery's OpenCursor:
{ from DBTables.Pas }
function TSession.DoOpenDatabase(const DatabaseName: string; AOwner: TComponent): TDatabase;
var
TempDatabase: TDatabase;
begin
Result := nil;
LockSession;
try
TempDatabase := nil;
try
Result := DoFindDatabase(DatabaseName, AOwner);
if Result = nil then
begin
TempDatabase := TDatabase.Create(Self);
TempDatabase.DatabaseName := DatabaseName;
TempDatabase.KeepConnection := FKeepConnections;
TempDatabase.Temporary := True;
Result := TempDatabase;
end;
Result.Open;
Inc(Result.FRefCount);
except
TempDatabase.Free;
raise;
end;
finally
UnLockSession;
end;
end;
As you can see, if the session can't find an existing TDatabase component with the right name, it creates a temporary one, and it's the call to Result.Open that pops up the login prompt, without, so far as I can see, giving you any opportunity to supply the password + user name before the pop-up (the Session's OnPassword doesn't seem to get called in the course of this).
Obviously you need to check using the debugger that that's what's happening in your app, a temporary TDatabase being created, I mean.
If what I've suggested in the Update below didn't work and I were desperate to avoid using a TDatabase component, I would look into the possibility of maybe deriving a TQuery descendant, and trying to override its OpenCursor to see if I could jam in the user name/password.
Anyway, seeing as you say you're not using an explicit TDatabase, if I understand you correctly, because of the "Temporary Table ..." issue, and seeing as the Session will create a temporary one anyway, I suppose it might be worth your while investigating why the temporary one doesn't provoke the "Temporary Table" error, whereas using a TDatabase component in your app evidently does. Idapi32.Cfg configuration issue, maybe? At the moment, I can't help you with that because I can't reproduce your "Temporary Table" error, despite using my TQuery to do a SELECT on a SqlServer table to return 250,000+ rows.
Oh, that's a point: Does your table contain any BLOBs? I seem to recall there's an Idapi config parameter that lets you reduce the temporary storage space the BDE uses for BLOBs (to zero, maybe, but it's been a long time since I used the BDE "for real").
Update: The thought just occurred to me that since your query seems to work with Session dynamically creating a TDatabase object, maybe it would also work with a TDatabase which you dynamically create yourself. I just tried the following, and it works for me:
procedure TForm1.DatabaseLogin(Database: TDatabase;
LoginParams: TStrings);
begin
LoginParams.Add('user name=sa');
LoginParams.Add('password=1234');
end;
procedure TForm1.Button1Click(Sender: TObject);
var
ADatabase : TDatabase;
begin
ADatabase := TDatabase.Create(Self);
ADatabase.AliasName := 'MAT41032';
ADatabase.DatabaseName := 'MAT41032';
ADatabase.SessionName := 'Default';
ADatabase.OnLogin := DatabaseLogin;
Query1.Open;
end;
+1 for an interesting question, btw.
On DatasnapServer I have :
TSQLConnection connected to my database.
SQLDataset1 (CommandType=ctQuery) that fetches data from my table (lets call it "RESORTS".
DataSetProvider1 is connected to my SQLDataset1.
DataSetProvider1 is set to AllowCommandText.
This works OK. Server starts without a problem. Data is obtained.
On the Client side I have :
SQLConnection1 which is connected OK.Driver is Datasnap.
DSProviderConnection1 is linked to my SQLConnection1.
Both connected without problem.
Then I have DataSource1 which is connected to a ClientDataSet1.
ClientDataSet1 is connected to my DataSetProvider1.
Setting it active retrieves the data from the server.
All displayed right in the grid.
On the Client form I have a Edit1 and a Button1.
I try and run a query using the ClientDataset1
procedure TForm2.Button1Click(Sender: TObject);
begin
ClientDataSet1.Close;
ClientDataSet1.CommandText := ' INSERT INTO RESORTS (RES_NAME) VALUES (:RN)';
ClientDataSet1.FieldByName('RN').AsString := Edit1.Text;
ClientDataSet1.Execute;
ClientDataSet1.Open;
end;
I get : ClientDataSet1: Field 'RN' not found.
So, I am wondering what is going on? Why cant I insert data with parameter?
If I substitute the parameter with :
ClientDataSet1.CommandText := ' INSERT INTO RESORTS (RES_NAME) VALUES ("TRY")';
I get :Remote error: SQLDataSet1: Cursor not returned from Query.
However, the data does get inserted.
What am I doing wrong here ?
(Rewritten based on new information provided by the poster in comments.)
Your entire approach is wrong. :-) You don't use parameters, SQL or CommandText. The TClientDataSet.CommandText documentation clearly says:
CommandText specifies what data the client dataset wants to receive from its (internal or external) provider. It is either:
An SQL statement (query) for the database server to execute.
The name of a table or stored procedure
An SQL statement (query) means only a SELECT is acceptable SQL. An INSERT is not a query, so it cannot be used in a CommandText to insert data.
To insert data in a TClientDataSet, you simply Insert or Append, and then use FieldByName to set the value, and then call the Post method:
ClientDataSet1.Insert;
ClientDataSet1.FieldByName('RES_NAME').AsString := Edit1.Text;
ClientDataSet1.Post;
To edit, you simply use Edit instead of Insert or Append; the rest stays exactly the same.
ClientDataSet1.Edit;
ClientDataSet1.FieldByName('RES_NAME').AsString := Edit1.Text;
ClientDataSet1.Post;
When you're ready to actually update the server data from the changes made in the TClientDataSet, call it's ApplyUpdates:
ClientDataSet1.ApplyUpdates(0);
You can use ClientDataSet1.ParamByName('RN').AsString := Edit1.Text;
I have a procedure when click a bitbutton, it open a dialog box to load some files, and add it into AdoQuery (AQSource1). When I add some files, this error appear :
"Multiple-step operation generater error. Check each status value."
Only when I add multiple files selected. But if I selected a file by a file there is no error at all... But sometimes if I select multiple files this error did not show up either.... Kind a confusing for me...
How to fix this ? in simple way...
PS:
I use Windows 7 Pro SP1 64bit, Embarcadero Delphi 2010
procedure TFMain1.btImgLoad1Click(Sender: TObject);
var i : integer;
strFilename : string;
begin
if OpenDialog1.Execute then
begin
// Add selected file to DBase and show it on DBGrid
for i := 0 to openDialog1.Files.Count-1 do
begin
// ShowMessage(openDialog1.Files[i]);
strfilename := openDialog1.Files[i];
AQSource1.Append;
AQSource1source_fileurl.Value := strFilename;
AQSource1source_filename.Value := ExtractFileName(strfilename);
AQSource1source_dateadd.Value := date();
AQSource1source_timeadd.Value := Time();
AQSource1.Post;
AQSource1.Close;
AQSource1.Open;
end;
end;
end;
Ah... Finally I found what the cause of it. It lies on the "Field size" in Access and AdoQuery in Delphi. The field size for both is 50. When I change them to 255, whola.... the error is gone....
So based on my conclusion, the error for "Multiple-step operation generater error. Check each status value." for my case was caused by the FIELD SIZE... Thanks ^^
this error usually occur when there is a values change on the server side and the changes are not being reflected on the client.for example when on/before insert trigger that change field value .
so all you need that is to change Adotable1.CursorLocation to the option clUseServer . no thing else.
good luck
I have similar experience, In one instance, when I have synthesized the required SQL text, and did not care about alias name & the ADO makes that alias automatically (which is a long name) this error occurs. the solution is to give an alias directly in the statement to by pass this short coming.
I'm working on a Delphi project with a MS SQL Server database, I connected the database with ADOConnection, DataSource and ADOProc components from Borland Delphi 7 and I added this code in behind:
procedure TForm1.Button2Click(Sender: TObject);
begin
ADOStoredProc1.ProcedureName := 'sp_Delete_Clen';
ADOStoredProc1.Refresh;
ADOStoredProc1.Parameters.ParamByName('#clenID').Value := Edit6.Text;
ADOStoredProc1.Active := True;
ADOStoredProc1.ExecProc;
end;
The component Edit6 is an editbox that takes the ID of the tuple that should be deleted from the database and ADOStoredProc1 is the stored procedure in the database that takes 1 parametar (the ID you want to delete).
The project runs with no problems, I even got a TADOTable and a DBGrid that load the information from the database, but when I try to delete a tuple from the database using its ID written in the EditBox I get this Error: "Cannot perform this operation on a closed dataset" and the breakpoint of the project is when the application tries to add the value for the 'clenID' parameter.
Where is my mistake and how to fix it?
I think the ADOStoredProc1.Refresh method is not appropriate here. In this case the stored procedure does not return a result set. Could you leave it out? And also the line ADOStoredProc1.Active := True. The connection to the database is open I presume? Could you also check the values of the Parameters collection in the Object Inspector?
I think you want to call ADOStoredProc1.Parameters.Refresh, not ADOStoredProc1.Refresh.
Also, you should only set Active to True if the SQL Server Stored procedure returns a dataset - i.e. the result of a SELECT statement. Setting Active to True is the same as calling Open.
If the stored procedure only returns a result code (RETURN n), then use ExecProc.
In no case should you use both ADOStoredProc1.Active := True; and ADOStoredProc1.ExecProc;
In summary, you probably want something like
procedure TForm1.btnDeleteClick(Sender: TObject);
begin
ADOStoredProc1.ProcedureName := 'sp_Delete_Clen';
ADOStoredProc1.Parameters.Refresh; // gets the parameter list from SQL Server
ADOStoredProc1.Parameters.ParamByName('#clenID').Value := edtID.Text;
ADOStoredProc1.ExecProc;
end;