Link to home
Start Free TrialLog in
Avatar of long8
long8

asked on

How to add Unicode strings to database?

[Env: Win2k AS, SQL Server 7.0]

Hi,

My database has field of 'ntext' type. I want to somehow programmatically add to it data continaing
Unicode chars, for example Japanese. How can I do this? Using ODBC? May be someone can give a sample?

Thanks in advance!
Avatar of DanRollins
DanRollins
Flag of United States of America image

How do you intend to connect to the database?  Will you be using ADO, OLEDB?  Is your program written using MFC?

-- Dan
Avatar of long8
long8

ASKER

ADO. Actually it does not matter. If you can give me working ODBC and OLEDB code I will accept your answer.
I'm now trying parameterized quiries in ADO...

Also I'm using sql server 2000, not 7.0, I mistaken.
THe thing is, you really don't need to do anything if you are using ADO.  As a COM object, it sjould work in UNICODE as its native tounge,\.  One needs to take pains to program in ANSI.  

When you assign a value to an ntext field, just make sure that you assign a UNICODE string.  What happens when you do code like this:

#define RsITEM(rs,x) rs->Fields->Item[_variant_t(x)]->Value

spRS->Open(... )
spRS->RsITEM("LastName")= _bstr_t(L"Jones");

-- Dan
Avatar of long8

ASKER

//I have UTF-8 Japanese string. I'm converting it to UNICODE:
int nTextLen=MultiByteToWideChar(CP_UTF8,0,"タテスカンナニチトシト",-1,NULL,0);
wchar_t *wszText=new wchar_t[nTextLen+1];
MultiByteToWideChar(CP_UTF8,0,"タテスカンナニチトシト",-1,wszText,nTextLen);

//Then I convert string to BCB's analogue of BSTR:
//C++Builder implements the WideString type as a class.
//WideString represents a string of wide characters
//(wchar_t). As such, it is useful when working with COM.

//WideString uses BSTRs in its underlying implementation. In
//addition to the usual string operators, the class includes
//methods for converting to or from BSTR values as well as
//for sharing the value of an existing BSTR.
WideString ws = WideString(wszText);

// Here is the code performing adding new row to database
ADOConnection1->Open("sa", "");
ADOQuery1->Connection = ADOConnection1;
ADOQuery1->SQL->Text = "INSERT INTO [MRATestProduct].[dbo].[PrTrack1] VALUES (4, :Description";
ADOQuery1->Parameters->ParamByName("Description")->Value = ws;

ADOQuery1->ExecSQL();
   
ADOQuery1->Connection = NULL;    
ADOConnection1->Close();    

Resulting row in database contains quotation marks ('?') instead of Japanese chars.

When I'm setting parameter value as bstr, like this:
ADOQuery1->Parameters->ParamByName("Description")->Value = ws->c_bstr();

I see the following error message: [Microsoft][ODBC SQL Server Driver][SQL Server]Line 1:Incorrect syntax near '@P1'.
Avatar of long8

ASKER

//I have UTF-8 Japanese string. I'm converting it to UNICODE:
int nTextLen=MultiByteToWideChar(CP_UTF8,0,"タテスカンナニチトシト",-1,NULL,0);
wchar_t *wszText=new wchar_t[nTextLen+1];
MultiByteToWideChar(CP_UTF8,0,"タテスカンナニチトシト",-1,wszText,nTextLen);

//Then I convert string to BCB's analogue of BSTR:
//C++Builder implements the WideString type as a class.
//WideString represents a string of wide characters
//(wchar_t). As such, it is useful when working with COM.

//WideString uses BSTRs in its underlying implementation. In
//addition to the usual string operators, the class includes
//methods for converting to or from BSTR values as well as
//for sharing the value of an existing BSTR.
WideString ws = WideString(wszText);

// Here is the code performing adding new row to database
ADOConnection1->Open("sa", "");
ADOQuery1->Connection = ADOConnection1;
ADOQuery1->SQL->Text = "INSERT INTO [MRATestProduct].[dbo].[PrTrack1] VALUES (4, :Description";
ADOQuery1->Parameters->ParamByName("Description")->Value = ws;

ADOQuery1->ExecSQL();
   
ADOQuery1->Connection = NULL;    
ADOConnection1->Close();    

Resulting row in database contains quotation marks ('?') instead of Japanese chars.

When I'm setting parameter value as bstr, like this:
ADOQuery1->Parameters->ParamByName("Description")->Value = ws->c_bstr();

I see the following error message: [Microsoft][ODBC SQL Server Driver][SQL Server]Line 1:Incorrect syntax near '@P1'.
ASKER CERTIFIED SOLUTION
Avatar of DanRollins
DanRollins
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Hi long8,
Do you have any additional questions?  Do any comments need clarification?

-- Dan
Avatar of long8

ASKER

Well, I've got it working using parameterized queries and your example! Great thanks!