Forum OpenACS Q&A: Query doesn't work

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Posted by nemaria nemaria on
There is a problem when running my program.
It connects to database all right, but doesn't print a query result but many blank rows instead(in loop, I sujest). Here is my code(copied from tutorial example. I run it on Visual Studio .Net):

#include "stdafx.h"
static OCIEnv *p_env;
static OCIError *p_err;
static OCISvcCtx *p_svc;
static OCIStmt *p_sql;
static OCIDefine *p_dfn = (OCIDefine *) 0;
static OCIBind *p_bnd = (OCIBind *) 0;

struct OCIEnv { };
struct OCIError { };
struct OCISvcCtx { };
struct OCIStmt { };
struct OCIDefine { };
struct OCIBind { };

void main()
{
int p_bvi;
char p_sli[20];
int rc;
char errbuf[100];
int errcode;

rc = OCIInitialize((ub4) OCI_DEFAULT, (dvoid *)0, /* Initialize OCI */
(dvoid * (*)(dvoid *, size_t)) 0,
(dvoid * (*)(dvoid *, dvoid *, size_t))0,
(void (*)(dvoid *, dvoid *)) 0 );

/* Initialize evironment */
rc = OCIEnvInit( (OCIEnv **) &p_env, OCI_DEFAULT, (size_t) 0, (dvoid **) 0 );

/* Initialize handles */
rc = OCIHandleAlloc( (dvoid *) p_env, (dvoid **) &p_err, OCI_HTYPE_ERROR,
(size_t) 0, (dvoid **) 0);
rc = OCIHandleAlloc( (dvoid *) p_env, (dvoid **) &p_svc, OCI_HTYPE_SVCCTX,
(size_t) 0, (dvoid **) 0);

/* Connect to database server */
rc = OCILogon(p_env, p_err, &p_svc, (OraText*)"scott", 5, (OraText*)"tiger", 5, (OraText*)"d458_nat", 8);
if (rc != 0) {
OCIErrorGet((dvoid *)p_err, (ub4) 1, (text *) NULL, &errcode, (OraText*)errbuf, (ub4) sizeof(errbuf), OCI_HTYPE_ERROR);
printf("Error - %.*s\n", 512, errbuf);
exit(8);
}

/* Allocate and prepare SQL statement */
rc = OCIHandleAlloc( (dvoid *) p_env, (dvoid **) &p_sql,
OCI_HTYPE_STMT, (size_t) 0, (dvoid **) 0);
rc = OCIStmtPrepare(p_sql, p_err, (OraText*)"select ename from emp where deptno=:x",
(ub4) 137, (ub4) OCI_NTV_SYNTAX, (ub4) OCI_DEFAULT);

/* Bind the values for the bind variables */
p_bvi = 10; /* Use DEPTNO=10 */
rc = OCIBindByName(p_sql, &p_bnd, p_err, (text *) ":x",
-1, (dvoid *) &p_bvi, sizeof(int), SQLT_INT, (dvoid *) 0,
(ub2 *) 0, (ub2 *) 0, (ub4) 0, (ub4 *) 0, OCI_DEFAULT);

/* Define the select list items */
rc = OCIDefineByPos(p_sql, &p_dfn, p_err, 1, (dvoid *) &p_sli,
(sword) 20, SQLT_STR, (dvoid *) 0, (ub2 *)0,
(ub2 *)0, OCI_DEFAULT);

/* Execute the SQL statment */
rc = OCIStmtExecute(p_svc, p_sql, p_err, (ub4) 1, (ub4) 0,
(CONST OCISnapshot *) NULL, (OCISnapshot *) NULL, OCI_DEFAULT);

while (rc != OCI_NO_DATA) { /* Fetch the remaining data */
printf("%s\n",p_sli);
rc = OCIStmtFetch(p_sql, p_err, 1, 0, 0);
}

rc = OCILogoff(p_svc, p_err); /* Disconnect */
rc = OCIHandleFree((dvoid *) p_sql, OCI_HTYPE_STMT); /* Free handles */
rc = OCIHandleFree((dvoid *) p_svc, OCI_HTYPE_SVCCTX);
rc = OCIHandleFree((dvoid *) p_err, OCI_HTYPE_ERROR);

return;
}
----------------------------------------------------------
Why? What's wrong? What can I do? I just want to print the query result.

The parameter length of OCIStmtPrepare function is 137, because 37 gives an error 'Exception.toString() failed'. Why?

I'm using oracle 9i.
Thanks in advance.