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
Related
When trying to make a request, it displays an error:
File is in use
How can I solve that program?
procedure TForm1.Button4Click(Sender: TObject);
var data,ffg:string;
begin
data:=formatdatetime('ddmm',(DateTimePicker1.Date));
Adoquery2.SQL.Clear;
adoquery2.SQL.text:='Delete from g_rabn where data=data';// deleting data from g_rabn
adoquery2.ExecSQL;
ShowMessage(SysErrorMessage(GetLastError));
end;
procedure TForm1.Button5Click(Sender: TObject);
begin
Adoquery3.close;
Adoquery3.SQL.Clear;
adoquery3.SQl.text:='pack table g_rabn';// packing tablr g_rabn
adoquery3.Open;
ShowMessage(SysErrorMessage(GetLastError));
end;
end.
I can not delete data from the table, they are marked as deleted but require packaging. How to do it programmatically? He writes that file is in use when packing what to do?
You should execute the statement, not open it as a query. One way to achieve that, is to run it using an TADOCommand, not an TADOQuery, or use the ExecSQL method of the TADOQuery.
Also, all other connections to the DBF must be closed, otherwise you can't get the exclusive access that you need for packing the table.
I found this thread from 2005 on another forum, where somebody made this work with two notable parameters:
Using the provider VFPOLEDB.1
Using just the command pack filename.dbf (without the table keyword).
Lastly, I'm not so sure about the line ShowMessage(SysErrorMessage(GetLastError));. This will show you the last API error, but that's on a low level. You are using the ADO components, so if anything is going wrong, you should expect ADO to throw an exception. For all you know ADO already worked around the issue one way or the other, and the error message you're seeing is not even relevant.
I am surprised that I could not get the solution suggested in Golez Troi's answer
to work, especially as it refers to a newsgroup post from someone who had seemingly managed to pack a dBASE table using ADO; as I said in a comment, if I try to call 'Pack xxxx' to pack a dBASE table via ADO, however I do it, I get
Invalid SQL Statement; DELETE, INSERT, PROCEDURE, SELECT or UPDATE expected
.
I was also surprised to notice something in the MS ODBC dBASE docs that I'd not noticed before, namely that the MS ODBC driver for dBASE files requires the BDE
Note
Accessing dBASE ISAM files through the ODBC Desktop Database Drivers requires installation of the Borland database engine
So, seeing as accessing dBASE files via Ado requires the BDE anyway, there seems to me to be
no point avoiding using the BDE to pack the dBASE table using the standard BDE method, namely to call DbiPackTable. I added a TDatabase and TTable
to my ADO test project, after which I was able to execute this code without any problem
procedure TForm1.Button2Click(Sender: TObject);
begin
try
// Insert code here to close any Ado object (TAdoConnection, TAdoCommand, etc) pointing
// at the dBASE table/file
// Also check that not Ado object pointing at it is open in the IDE
//
// Then ...
Database1.DatabaseName := 'MADBF2';
Database1.Connected := True;
Table1.TableName := 'MATest.Dbf';
Table1.Exclusive := True;
Table1.Open;
// Following uses a call to DbiPackTable to pack the target table
Check(DbiPackTable(Table1.DBHandle, Table1.Handle, nil, nil,True));
finally
Table1.Close;
Database1.Connected := False;
end;
end;
FWIW, while I was writing this answer, I noticed that the BDE.Int file (which gives the declarations but not the implementation of the BDE interface) was on the D7 distribution CD but was apparently not installed by default).
I have XE8 and the version of InterbaseXE7 that comes with it installed on two machines, A & B. Using IBX or DBX I can connect to the IB server running on the same machine and access its databases without any problem. Btw, I am not a regular IB user.
I had no luck at all connecting from a Delphi app on machine A to an IB database on machine B: I got all manner of errors including a mystifying one about not being able to find the file specified (despite doing a DIR from a CMD prompt to verify that I had the name right) until I discovered that in those circumstances (connecting to a remote server), the database name has to be capitalized in the Delphi app on A exactly as it is on the db host B.
So, assuming there is no way to configure IB and/or IBX to avoid this case-sensitivity, how can I programmatically retrieve a list of the database names, correctly capitalized, on B (assuming I have no access to B's file-system) from a Delphi app on A?
I've tried using the TIBServerProperties component to do this but using code like this:
procedure TForm1.btnPropertiesClick(Sender: TObject);
var
S : String;
begin
IBServerProperties1.Active := True;
IBServerProperties1.FetchDatabaseInfo;
S := IBServerProperties1.DatabaseInfo.DbName[0];
Caption := S;
end;
, the database names are returned from the IB host server in all capitals, which obviously doesn't solve the problem of finding their correct capitalizations.
It turns out that the TIBServerProperties can get DB Aliases from a remote server with the correct capitalization, but not using the DatabaseInfo property. The information can be obtained from its AliasInfo property instead (one of those things that's kind-of obvious with the benefit of hindsight), as shown below.
procedure TForm1.btnPropertiesClick(Sender: TObject);
var
S : String;
i : Integer;
begin
IBServerProperties1.Active := True;
IBServerProperties1.FetchAliasInfo;
for i :=0 to IBServerProperties1.AliasCount - 1 do begin
S := IBServerProperties1.AliasInfo[i].Alias; // <- the .Alias has the
// same capitalization as on the server
S := S + ' ' + IBServerProperties1.AliasInfo[i].DBPath;
Memo2.Lines.Add(S);
end;
end;
, which is good enough for my immediate purpose.
I'd still be interested to know, though, if there is an IB configuration parameter or similar that avoids the case-sensitivity that provoked my q.
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.
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;