Using SQL Server connection string with firedac - sql-server

Using Delphi 10.2, I am trying to use a standard SQL Server connection string with Firedac, but can't seem to make it work.
This is my connection string:
Data Source=PSI-PC006\MSSQL2008;Initial Catalog=PlayGround;Integrated Security=True;Pooling=False;
My code is simply:
function tdmMain.doConnect(const connection : string) : boolean;
begin
dmConnect.cnxData.ConnectionString := connection;
dmConnect.cnxData.DriverName := 'MSSQL';
try
dmConnect.cnxData.Connected := true;
result := true;
except
on E:Exception do
begin
ShowMessage('Connection error' + e.Message);
result := false;
end;
end;
end;
I am trying to make it so that I don't have to load from an ini file, that my application can just be called with the connection string.
Is this even possible?

You don't need to do what you are trying, in order to set up the connection string.
Just double-click your FDConnection1 in the IDE form editor then, in the "FireDAC Connection Editor" pop-up, on the Definition tab, just fill in the parameters you need to specify to make the connection.
Using the FireDAC Connection Editor sets the Params property of your FDConnection. If you want to adjust the FD equivalent of the MSSS Connection String at runtime, you can do direct assignments to the parameter values as per usual.

The FireDac connection string is not same as a SQL Server connection string. It also includes the driver name so you do not need to do that separately.
Server=PSI-PC006\MSSQL2008;OSAuthent=Yes;Database=PlayGround;DriverID=MSSQL
If you use the connection configuration dialog box in the Delphi UI you can see the name=value pairs by clicking on the .. to the right of the Parameters property. The connection string is just those name=:value pairs separated by semicolons.

Related

Storing Files in SQL Server Table (varbinary(max) column) using ADOQuery Component

I'm using SQL Server 2019 and Delphi 10.3.
I need to store any kind of files ( like pdf, txt, docx, etc) in a 'Personal_Files' table.
This table is composed by a column with the file extension ( as varchar) and a varbinary(max) column to store the file itself.
I did some research on how to store these files on a table, but without success. Below some example:
var
Input,Output: TStream;
FName: TFileName;
begin
...
//Create Streams and encode Base64:
Input := TFileStream.Create(FName,fmOpenRead);
Output := TFileStream.Create(FName+'Temp',fmCreate);
TNetEncoding.Base64.Encode(Input,Output);
... // Some validations
// In the ADOQuery component, I did this:
with ADOQuery, sql do
begin
close;
clear;
add('INSERT INTO MyDatabase.dbo.MyFilesTable (EXTENSION,FILEBIN)');
add('VALUES (:wextension, :wfilebin)');
Parameters.ParamByName('wextension').Value := TPath.GetExtension(FName);
Parameters.ParamByName('wfilebin').Value := Output.toString;
ExecSQL;
end;
In this example, I tried to parse the stream as String, after the encode, but when I look in the SQL Table, it's the same stream for all the archives I tried. The parameter doesn't accept TStream type. Thank you in advance.
After some research, and some advices, I found a way to send the file to my SQL Server table with ADOQuery. Altough, I learned that this isn't recommended, so it's just to answer my question directly:
Just a change on the final part of the code answers my question ( but again, it's not the recommended way to store files, as commented on the question.):
with ADOQuery, sql do
begin
close;
clear;
add('INSERT INTO MyDatabase.dbo.MyFilesTable (EXTENSION,FILEBIN)');
add('VALUES (:wextension, :wfilebin)');
Parameters.ParamByName('wextension').Value := TPath.GetExtension(FName);
Parameters.Items[1].LoadFromStream(Output,ftVarBytes);
ExecSQL;
end;
Just changing the way I was setting the parameter solved the problem. In this example, using the 'LoadFromStream' on the Paremeters.Items[n], where n is the parameter index, it worked very well. The ftVarBytes is the field type parameter.

Datasnap Delphi XE5 Server side dynamic sql

I am having a small problem with datasnap in delphi Xe5.
I need to run dynamic queries on the server side. I am using an ADO connection on the server methods.
Server Procedure:
var
qryNew: TADOQuery;
dspNew: TDatasetProvider;
begin
qryNew := TADOQuery.Create(nil);
qryNew.Connection := Adoconnection1;
qryNew.SQL.Text := SQL;
qryNew.Name := 'qry'+IntToStr(1);
dspNew := TDatasetProvider.Create(nil);
dspNew.Name := 'dsp'+IntToStr(1);
dspNew.Dataset := qryNew;
qryNew.Open;
Result := dspNew.Name;
end;
Client side procedure:
ClientDataset1.ProviderName :=clientmodule3.ServerMethods1Client.GetDataForClient('Select top 10 * from ODBC.trans_day_2009_1111;');
On the main form i have a SQLconnection, DSProvider connection and a client dataset. When I try to set the provider name for the client with the above code, i get the error "Remote error: Provider not exported : DSP1"
Usually (not always), error messages are helpful if you spend the time to understand them. If it says the provider is not exported, you should have checked why it wasn't - i.e. the doc says:
"To enable the remote data module to pass calls to the provider, the provider's Exported property must be True, and its Owner property must specify the remote data module."
http://docwiki.embarcadero.com/Libraries/XE5/en/Datasnap.Provider.TDataSetProvider
Your provider has no owner.

How to make ADO parameter to update SQL Server datetime column?

edit I should have mentioned that I'm trying to do this with Delphi 2006.
OK, I think I have hit on a question with no previous answers.
I have a SQL Server database with columns of type datetime. When I try to insert a row with a parametrized command, I get
Exception class EOleException with message
'[Microsoft][ODBC SQL Server Driver]Optional feature not implemented'.
My insert procedure looks like this:
procedure TForm1.btnZoomClick(Sender: TObject);
const
InsCmd = 'insert into dbo.foo (added, edited, editor, narrative) ' +
'values (:dateAdded, :dateEdited, :theEditor, :theNarrative);';
begin
dmDbToy2.DataModule2.ADOCommand1.CommandText := InsCmd;
with DataModule2.ADOCommand1.Parameters do
begin
// the following line was an attempt to trick VarAsType into making a
// adDbTimeStamp: VarAsType is having none of it.
// FindParam('dateAdded').Value := VarAsType(VarFromDateTime(Now), 135);
FindParam('dateAdded').Value := VarFromDateTime(Now);
FindParam('dateEdited').Value := Null;
FindParam('theEditor').Value := 'wades';
FindParam('theNarrative').Value := Null;
end;
DataModule2.ADOCommand1.Execute;
end;
I found some postings via google which seem to indicate that SQL Server wants a adDbTimeStamp type to update these columns, but VarAsType does not want to make one for me.
Is there a way to create a value for the dateAdded and dateEdited parameters in the code sample?
In the comments thread on the original question, user RRUZ made a suggestion that turned out to resolve the issue: The problem was with the provider. Namely, I was using the OLEDB Provider for ODBC rather than the OLEDB Provider for SQL Server. Changing the provider as suggested made the 'Optional feature not implemented' error message go away and enabled the insert to work with a simple assignment of TDateTime to TParameter.Value, thusly:
FindParam('dateAdded').Value := Now;
Set the datatype for the parameter, it might do a difference in how the parameters is treated. I would also recommend that you use ParamByName instead of FindParam. With ParamByName you get a Param xx not found exception if the parameters does not exist in the Parameters collection. FindParam returns nil if it is not found. I have never needed to use any variant conversion stuff when assigning parameters for a TADOCommand so think you should remove that as well.
Try this.
with ParamByName('dateAdded') do
begin
DataType := ftDateTime;
Value := Now;
end;
with ParamByName('dateEdited') do
begin
DataType := ftDateTime;
Value := Null;
end;
with ParamByName('theEditor') do
begin
DataType := ftString; // or ftWideString if you use nchar/nvarchar
Value := 'wades';
end;
with ParamByName('theNarrative') do
begin
//DataType := ftString // Don't know datatype here
Value := Null;
end;
Just set the parameter as a datetime. I do it all the time in ADO and other conection layers
DataModule2.ADOCommand1.Parameters.ParamByName('dateAdded').Value := Now();
//other code
DataModule2.ADOCommand1.Parameters.ParamByName('dateEdited').Value := Null;
//other code
DataModule2.AdoCommand1.Execute;

Delphi 5.0 Open Interbase/FireBird connection via code

This is old stuff! Is related to delphi 5.0 and interbase 1.6.
I'm trying to open a DB connection via code. But this code is related to enabling the connection, all the components were added using delphi drag-drop User Interface: DataSource1, TForm1, DBGrid, DBNavigator etc..
procedure TDataModule2.DataModuleCreate(Sender: TObject);
begin
database.DatabaseName:='C:\MyDatabase.GDB';
database.Connected := true;
database.Open;
IBTransaction.Active := true;
myTable.Open;
end;
I have a TForm with DBGrid and DBNavigator component. I also have a TIBQuery (that DataSource1 is associated to) with this code on the SQLStrings:
SELECT * FROM NEW_TABLE
On the Form I have this code to enable DBNavigator and DBGrid to show the DB Values. The DB is very simple is just a table: NEW_TABLE with a NEW_VALUE of VARCHAR type
procedure TForm1.FormCreate(Sender: TObject);
begin
DataSource1.DataSet.Open;
// This will call the query associated to this DataSource1 the tibQuery1 to call
// SELECT * FROM NEW_TABLE, but the message below appears: IBClientError...
end;
The message appears:
IBClientError with message 'Database not assigned'
OBS1: If I connect the components by hand on delphi user interface, the connection with the DB is established.
You have to assign the Database property of your query, something like:
IBQuery1.Database := MyDatabase;

Delphi: "Parameter object is improperly defined. Inconsistent or incomplete information was provided."

I'm trying to insert a record into a table in a 3-tier database setup, and the middle-tier server generates the error message above as an OLE exception when it tries to add the first parameter to the query.
I've Googled this error, and I find the same result consistently: it comes from having a colon in a string somewhere in your query, which b0rks ADO's SQL parser. This is not the case here. There are no spurious colons anywhere. I've checked and rechecked the object definition against the schema for the table I'm trying to insert into. Everything checks out, and this has my coworkers stumped. Does anyone know what else could be causing this? I'm at my wits' end here.
I'm using Delphi 2007 and SQL Server 2005.
I can get this error, using Delphi 2007 and MSSQL Server 2008, and I found a workaround. (which is pretty crappy IMHO, but maybe its useful to you if yours is caused by the same thing.)
code to produce the error:
with TADOQuery.Create(nil)
do try
Connection := ADOConnection;
SQL.Text := ' (SELECT * FROM Stock WHERE InvCode = :InvCode ) '
+' (SELECT * FROM Stock WHERE InvCode = :InvCode ) ';
Prepared := true;
Parameters.ParamByName('InvCode').Value := 1;
Open; // <<<<< I get the "parameter object is...etc. error here.
finally
Free;
end;
I found two ways to fix it:
1) remove the brackets from the SQL, ie:
SQL.Text := ' SELECT * FROM Stock WHERE InvCode = :InvCode '
+' SELECT * FROM Stock WHERE InvCode = :InvCode ';
2) use two parameters instead of one:
with TADOQuery.Create(nil)
do try
Connection := ADOConnection;
SQL.Text := ' (SELECT * FROM Stock WHERE InvCode = :InvCode1 ) '
+' (SELECT * FROM Stock WHERE InvCode = :InvCode2 ) ';
Prepared := true;
Parameters.ParamByName('InvCode1').Value := 1;
Parameters.ParamByName('InvCode2').Value := 1;
Open; // <<<<< no error now.
finally
Free;
end;
I found this thread while searching the previously mentioned Exception message. In my case, the cause was an attempt to embed a SQL comment /* foo */ into my query.sql.text.
(I thought it would have been handy to see a comment go floating past in my profiler window.)
Anyhow - Delphi7 hated that one.
Here a late reply. In my case it was something completely different.
I tried to add a stored procedure to the database.
Query.SQL.Text :=
'create procedure [dbo].[test]' + #13#10 +
'#param int ' + #13#10 +
'as' + #13#10 +
'-- For the parameter you can pick two values:' + #13#10 +
'-- 1: Value one' + #13#10 +
'-- 2: Value two';
When I removed the colon (:) it worked. As it saw the colon as a parameter.
I just encountered this error myself. I'm using Delphi 7 to write to a 2003 MS Access database using a TAdoQuery component. (old code) My query worked fine directly in MS Access, but fails in Delphi through the TAdoQuery object. My error came from a colon (apologies to the original poster) from a date/time value.
As I understand it, Jet SQL date/time format is #mm/dd/yyyy hh:nn:ss# (0 left-padding is not required).
If the TAdoQuery.ParamCheck property is True then this format fails. (Thank you posters!) Two work-arounds are: a) set ParamCheck to False, or b) use a different date/time format, namely "mm/dd/yyyy hh:nn:ss" (WITH the double quotes).
I tested both of these options and they both worked.
Even though that double-quoted date/time format isn't the Jet date/time format, Access is pretty good at being flexible on these date/time formats. I also suspect it has something to do with the BDE/LocalSQL/Paradox (Delphi 7's native SQL and database engine) date/time format (uses double quotes, as above). The parser is probably designed to ignore quoted strings (double quotes are the string value delimiter in BDE LocalSQL), but may stumble somewhat on other non-native date/time formats.
SQL Server uses single quotes to delimit strings, so that might work instead of double quotes when writing to SQL Server tables (not tested). Or maybe the Delphi TAdoQuery object will still stumble. Turning off ParamCheck in that case may be the only option. If you plan to toggle the ParamCheck property value in code, you'll save some processing time by ensuring the SQL property is empty before enabling it, if you're not planning on parsing the current SQL.
I'm facing the same error described in your question. I've traced the error into ADODB.pas -> procedure TParameters.AppendParameters; ParameterCollection.Append(Items[I].ParameterObject).
By using breakpoints, the error was raised, in my case, by a parameter which should fill a DateTime field in the database and I've never filled up the parameter. Setting up the parameter().value:='' resolved the issue (I've tried also with varNull, but there is a problem - instead of sending Null in the database, query is sending 1 - the integer value of varNull).
PS: I know is a 'late late late' answer, but maybe somebody will reach at the same error.
If I remember well, you have to explicit put NULL value to the parameter. If you are using a TAdoStoredProc component, you should do this in design time.
Are you using any threading? I seem to remember getting this error when a timer event started a query while the ADO connection was being used for another synchronous query. (The timer was checking a "system available" flag every minute).
Have you set the DataType of the parameter or did you leave it as ftUnknown?
I have also had the same problem, but with a dynamic command (e.g. an Update statement).
Some of the parameters could be NULL.
The only way i could get it working, was setting the parameter.DataType := ftString and parameter.Size := 1 and not setting the value.
cmdUpdate := TADOCommand.Create(Self);
try
cmdUpdate.Connection := '**Conections String**';
cmdUpdate.CommandText := 'UPDATE xx SET yy = :Param1 WHERE zz = :Param2';
cmdUpdate.Parameters.ParamByName('Param2').Value := WhereClause;
if VarIsNull(SetValue) then
begin
cmdUpdate.Parameters.ParamByName('Param1').DataType := ftString;
cmdUpdate.Parameters.ParamByName('Param1').Size := 1;
end else cmdUpdate.Parameters.ParamByName('Param1').Value := SetValue;
cmdUpdate.Execute;
finally
cmdUpdate.Free;
end;
I just ran into this error today on a TADOQuery which has ParamCheck := False and has no colons in the SQL.
Somehow passing the OLECMDEXECOPT_DODEFAULT parameter to TWebBrowser.ExecWB() was causing this for me:
This shows the problem:
pvaIn := EmptyParam;
pvaOut := EmptyParam;
TWebBrowser1.ExecWB(OLECMDID_COPY, OLECMDEXECOPT_DODEFAULT, pvaIn, pvaOut);
This does not show the problem:
pvaIn := EmptyParam;
pvaOut := EmptyParam;
TWebBrowser1.ExecWB(OLECMDID_COPY, OLECMDEXECOPT_DONTPROMPTUSER, pvaIn, pvaOut);
A single double quote in the query can also raise this error from what I just experienced and I am not using parameters at all ...
You can get this error when attempting to use a time value in the SQL and forget to wrap it with QuotedStr().
I got the same error. Turned out, that it is because a parameter of the stored procedure was declared as varchar(max). Made it varchar(4000) and error disappeared.

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