Re: FW: Libpq - multibyte character support

["Pradeepkumar, Pyatalo (IE10)" <Pradeepkumar.Pyatalo@xxxxxxxxxxxxx>]

The problem that I am facing is not with creating the database to support multi bytes. I have a code written in C/C++. I am using libpq functions to do the database operations. But the problem is the libpq functions accept the database queries only in the form of char * . It does not accept wchar_t * If i have to execute a query say "SELECT * FROM GSNAMES WHERE GSName = 'some chinese_string'"....i am not able to pass the paramater to the libpq function PQexe(PGconn *, char *). I need help regarding this.

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From: Miguel Higuera [mailto:miguelstratoss@xxxxxxxxx]
Sent: Wednesday, September 07, 2005 10:34 AM
To: Pradeepkumar, Pyatalo (IE10); pgsql-admin@xxxxxxxxxxxxxx
Subject: Re: [ADMIN] FW: Libpq - multibyte character support

CREATE DATABASE name ENCODING = WIN1256

THIS MAY BE THE 
SOLUTION
ALSO YOU CAN PROBE WITH :
ALT, LATIN1 TO LATIN9, EUC_CN, 
EUC_JP,EUCCREATE DATABASE name ENCODING = WIN1256

THIS MAY BE THE 
SOLUTION
ALSO YOU CAN PROBE WITH :
ALT, LATIN1 TO LATIN9, EUC_CN, 
EUC_JP,EUC_KR......................

I WAIT THIS BE 
USEFULL
_KR......................

I WAIT THIS BE USEFULL

2005/9/6, Pradeepkumar, Pyatalo (IE10) <Pradeepkumar.Pyatalo@xxxxxxxxxxxxx>:

Hi all,

My question is does PgSQL libpq functions support multibyte characters...if not then is there a way to provide multibyte data to Postgres using libpq functions. The other question is does Postgres support Chinese characters....if I insert chinese characters into a table, when I read, will I get the same chinese characters. Please help me out in this regard.

I have created a database with UNICODE support which has a table GSNames(Gsname varchar(40), status int, errorcode int)
I tried to insert into this table from a simple C program using libpq functions....but it gives error as libpq does not support wchar datatypes. Here is the code -

int main()
{
//      wchar_t szQuery[255];
        char szQuery[255];

        PGconn *DBCon;
        PGresult *DBResult;

        //Connect to the database with default settings
        DBCon = PQsetdbLogin(NULL, NULL, NULL, NULL, "test1", "postgres", ""); //test1 is database created with UNICODE encoding

        //check if there is any error in connecting to the database
        if(PQstatus(DBCon) == CONNECTION_BAD)
        {
                fprintf(stderr,"\nGetAttributeInfo(): Connection to database failed.");
                fprintf(stderr,"\nGetAttributeInfo(): %s", PQerrorMessage(DBCon));
                return ERROR_DB_CON;
        }
        else
        {
                fprintf(stderr,"\nGetAttributeInfo(): Connection to database successful.");
        }
       
        //form the DELETE command as character buffer.
        //swprintf(szQuery,500,L"INSERT INTO gsnames values('×¢²á',2,2)");
        sprintf(szQuery,"INSERT INTO gsnames values('×¢²á',2,2)");

        //execute the command.
        DBResult = PQexec(DBCon, (char *)szQuery);

        //check for any errors in executing the query.
        if(PQresultStatus(DBResult) != PGRES_COMMAND_OK)
        {
                fprintf(stderr,"\nGetAttributeInfo(): %s", PQresultErrorMessage(DBResult));
                PQclear(DBResult);
                PQfinish(DBCon);
                return ERROR_DB_EXEC;
        }
        else
        {
                fprintf(stderr,"\nDBInsertPointAttribute(): Insertion successful. No. of rows affected = %d.", PQntuples(DBResult));

        }

        PQclear(DBResult);
        PQfinish(DBCon);

        return 0;
}

The problem is I am not able to pass multibyte characters to postgres. Please help.....Thanks in advance.

Between I am using Postgres version 7.4.3. While installing Pgsql, I dnt specify any encoding or multi byte character support for initdb.




Regs,
Pradeep