Oracle OCI编程流程

这是在做OCI开发时写的一些测试的代码，基本流程很简单如下：

>>创建环境句柄 OCIEnvCreate(&envhp,OCI_DEFAULT,(dvoid *)0, 0,0,0,0,(dvoid **)0);
>>申请错误句柄 OCIHandleAlloc((dvoid *) envhp,(dvoid **)&errhp, OCI_HTYPE_ERROR,(size_t)0,(dvoid **)0);
>>申请服务器句柄 OCIHandleAlloc((dvoid *)envhp,(dvoid **)&srvhp, OCI_HTYPE_SERVER,(size_t)0,(dvoid **)0);
>>申请服务环境句柄 OCIHandleAlloc((dvoid *)envhp,(dvoid **)&svchp, OCI_HTYPE_SVCCTX,(size_t)0,(dvoid **)0);
>>设置服务环境的服务器属性 OCIAttrSet((dvoid *)svchp,OCI_HTYPE_SVCCTX, (dvoid *)srvhp,(ub4)0,OCI_ATTR_SERVER,(OCIError *)errhp);
>>连接数据库，建立会话 status = OCILogon(envhp,errhp,&svchp,(const OraText*)user,(ub4)strlen((char *)user), (text *)pass_word,(ub4)strlen((char *)pass_word),(text *)servername,(ub4)strlen((char *)servername));

>>申请语句句柄 OCIHandleAlloc((dvoid *)envhp,(dvoid **)&stmthp, OCI_HTYPE_STMT,(size_t)0,(dvoid **)0);
>>准备sql语句 OCIStmtPrepare(stmthp,errhp,(const OraText*)sqlstat, (ub4)strlen((char *) sqlstat),OCI_NTV_SYNTAX,OCI_DEFAULT));
>>定义输出变量 OCIDefineByPos(stmthp,&defhp[0],errhp,1,&sum, sizeof(sum),SQLT_INT,(sb2 *)0,0,(ub2 *)0,OCI_DEFAULT) );
>>执行sql语句 OCIStmtExecute(svchp,stmthp,errhp,(ub4)0, (ub4)0,(const OCISnapshot *)NULL, (OCISnapshot *)NULL, OCI_DEFAULT);

>>取结果OCIStmtFetch(stmthp,errhp,1,OCI_FETCH_NEXT,OCI_DEFAULT);

>>断开连接 OCILogoff(svchp,errhp);

几个需要注意的地方：

1.输出变量（存储过程参数除外）用OCIDefineByPos

2.在调用存储过程时要用OCIBindByPos绑定所有参数

3.Oracle存储过程返回结果集不像mysql和sqlserver，需要用cursor OUT出来，在程序中接收cursor让很多人很迷惑，cursor需要用OCIStmt来绑定，然后和正常STMT一样来读取结果


如果还有不懂的地方，下面是示例代码：

#include "OCI.h" 
#include <conio.h>
#include <stdio.h>
#include <string>
#include <Windows.h>

using namespace std;

const char user[31] = "alien"; 
const char pass_word[31] = "alienchang"; 
const char servername[31] = "orcl"; 

void read();
void procedure();

typedef sword (*FuncOCIEnvCreate)(OCIEnv**,ub4, void*, void* (*malocfp)(void*, size_t),void* (*ralocfp)(void*, void*,size_t),void (*mfreefp)(void*, void*),size_t, void**);

void error_proc(dvoid *errhp, sword status) 
{ 
	text errbuf[512]; 
	sb4 errcode; 
	switch (status) 
	{ 
	case OCI_SUCCESS: 
		// printf("OCI_success\n"); 
		break; 
	case OCI_SUCCESS_WITH_INFO: 
		printf("OCI error: OCI_success_with_info\n"); 
		break; 
	case OCI_NEED_DATA: 
		printf("OCI error: OCI_need_data\n"); 
		break; 
	case OCI_NO_DATA: 
		printf("OCI error: OCI_no_data\n"); 
		break; 
	case OCI_ERROR: 
		(void)OCIErrorGet((dvoid *)errhp,(ub4)1,NULL,&errcode, 
			errbuf,(ub4)sizeof(errbuf),OCI_HTYPE_ERROR); 
		printf("错误号：%d\n错误信息：%s\n",errcode,errbuf); 
		break; 
	case OCI_INVALID_HANDLE: 
		printf("OCI error: OCI_invalid_handle\n"); 
		break; 
	case OCI_STILL_EXECUTING: 
		printf("OCI error: OCI_still_executing\n"); 
		break; 
	default: 
		break; 
	} 

} 

void main () 
{
	procedure();
	return ; 
} 

void procedure()
{
	OCIEnv *envhp = NULL;
	OCIError *errhp = NULL;
	OCIServer *srvhp = NULL;
	OCISvcCtx *svchp = NULL;
	OCIStmt *stmthp = NULL;
	OCIStmt *curstmthp = NULL;
	OCIBind *bndlp[3];
	OCIDefine *defhp[3];
	char account[30] = "D5SJ53WE06";
	int number = 0;
	sword status = 0;
	ub2 type = 0;
	char* sqlstat = "begin say(:v_text, :v_num); end;";//"begin pak_rc.get(:v_account, :v_cursor); end;"; 


	OCIEnvCreate(&envhp, OCI_DEFAULT, 0, 0, 0, 0, 0, (dvoid**)0);
	OCIHandleAlloc(envhp, (dvoid**)&errhp, OCI_HTYPE_ERROR, 0, (dvoid**)0);
	error_proc(errhp, OCIHandleAlloc((dvoid*)envhp, (dvoid**)&srvhp,
		OCI_HTYPE_SERVER, 0, (dvoid**)0));
	error_proc(errhp, OCIHandleAlloc((dvoid*)envhp, (dvoid**)&svchp,
		OCI_HTYPE_SVCCTX, 0, (dvoid**)0));

	status = OCILogon(envhp, errhp, &svchp, (const OraText*)user, (ub4)strlen(user),
		(const OraText*)pass_word, (ub4)strlen(pass_word), (const OraText*)servername, (ub4)strlen(servername));

	if ( OCI_SUCCESS == status )
		printf("Connect Successsfully!\n");
	else{
		printf("Connect Failed!");
		error_proc(errhp, status);
		return;
	}

	error_proc(errhp, OCIHandleAlloc((dvoid*)envhp, (dvoid**)&stmthp,
		OCI_HTYPE_STMT, 0, (dvoid**)0));

	error_proc(errhp, OCIHandleAlloc((dvoid*)envhp, (dvoid**)&curstmthp,
		OCI_HTYPE_STMT, 0, (dvoid**)0));

	error_proc(errhp, OCIStmtPrepare(stmthp, errhp, (const OraText*)sqlstat,
		(ub4)strlen(sqlstat), OCI_NTV_SYNTAX, OCI_DEFAULT));

	/*error_proc(errhp, OCIDefineByPos(stmthp, &defhp[0], errhp, 2, &curstmthp,
		0, SQLT_RSET, (ub2*)0, 0, (ub2*)0, OCI_DEFAULT));

	char test[32];*/

	int pnum = 0;
	OCIParam *param;
	/*error_proc(errhp, OCIAttrGet ((dvoid *)stmthp, (ub4)OCI_HTYPE_STMT,
		(dvoid *)&pnum, (ub4 *)0, (ub4)OCI_ATTR_PARAM_COUNT,
		errhp));*/
	/*error_proc(errhp, OCIParamGet (stmthp, OCI_HTYPE_STMT, errhp,
		(dvoid **)¶m, 1));
	error_proc(errhp, OCIAttrGet (param, OCI_DTYPE_PARAM,
		(dvoid *)&type, (ub4 *)0, OCI_ATTR_DATA_TYPE, errhp));*/
	printf("%d type: %d\n", pnum, type);
	printf("%d: %d %d: %d", account, &account, &curstmthp, curstmthp);
	
	error_proc(errhp, OCIBindByPos(stmthp, &bndlp[0], errhp, 1, &account, strlen(account) + 1,
		SQLT_STR, NULL, NULL, NULL, 0, NULL, (ub4)OCI_DEFAULT));
	error_proc(errhp, OCIBindByPos(stmthp, &bndlp[1], errhp, 2, &number, sizeof(number),
		SQLT_INT, NULL, NULL, NULL, 0, NULL, (ub4)OCI_DEFAULT));
	/*error_proc(errhp, OCIBindByPos(stmthp, &bndlp[1], errhp, 2, &curstmthp, sizeof(curstmthp),
		SQLT_RSET, NULL, NULL, NULL, 0, NULL, (ub4)OCI_DEFAULT));*/
	

	/*error_proc(errhp, OCIDefineByPos(stmthp, &defhp[0], errhp, 1,(dvoid *)test,
		(sb4)sizeof(test), SQLT_STR, (ub2*)0, 0, (ub2*)0, OCI_DEFAULT));*/

	if ( (status = OCIStmtExecute(svchp,stmthp,errhp,(ub4)1, 
		(ub4)0,(const OCISnapshot *)NULL, (OCISnapshot *)NULL, 
		OCI_COMMIT_ON_SUCCESS)) && status != OCI_SUCCESS_WITH_INFO )
	{
		error_proc(errhp, status);
		printf("-----ora_search,error in OCIStmtexecute-----\n"); 
		return;
	}
	printf("string: %s; number: %d\n", account, number);
	getch(); 

	int num = 0;
	/*error_proc(errhp, OCIAttrGet ((dvoid *)curstmthp, (ub4)OCI_HTYPE_STMT,
		(dvoid *)&num, (ub4 *)0, (ub4)OCI_ATTR_PARAM_COUNT,
		errhp));
	printf("%d\n", num);

	char c_account[64], pwd[64];
	error_proc(errhp, OCIDefineByPos(curstmthp, &defhp[1], errhp,1, c_account, sizeof(account), 
		SQLT_STR, (ub2)0, 0, 0,OCI_DEFAULT)); 
	error_proc(errhp, OCIDefineByPos(curstmthp, &defhp[2], errhp,2, pwd, sizeof(pwd), 
		SQLT_STR, (ub2*)0, 0, 0,OCI_DEFAULT)); 

	error_proc(errhp,OCIStmtFetch(curstmthp,errhp,1,OCI_FETCH_NEXT,OCI_DEFAULT));

	do
	{
		printf("status: %d Account:%s PWD:%s\n", status, c_account, pwd);
		status = OCIStmtFetch(stmthp,errhp,1,OCI_FETCH_NEXT,OCI_DEFAULT);
	}while( OCI_SUCCESS == status );*/

	//断开连接 
	error_proc(errhp,OCILogoff(svchp,errhp)); 
	OCIHandleFree(errhp, OCI_HTYPE_ERROR); 
}

void read()
{
	OCIEnv *envhp = NULL; //环境句柄 
	OCIError *errhp = NULL; //错误句柄 
	OCIServer *srvhp = NULL; //服务器句柄 
	OCISvcCtx *svchp = NULL; //服务环境句柄 
	OCIStmt *stmthp = NULL; //语句句柄 
	OCIBind *bnd1p = (OCIBind *)0; //结合句柄 
	OCIDefine *defhp[5]; //定义句柄 
	sword status; 
	int sum; //命中记录数 
	char account[50];
	char* sqlstat = "select id,account from hx_account"; 
	int li_ret; 

	li_ret = 0; 

	// char *summary_element=" rec_ctrl_id,title,first_author,book_search_no,publisher"; 

	//创建环境句柄 
	OCIEnvCreate(&envhp,OCI_DEFAULT,(dvoid *)0, 
		0,0,0,0,(dvoid **)0);
	//申请错误句柄 
	OCIHandleAlloc((dvoid *) envhp,(dvoid **)&errhp, 
		OCI_HTYPE_ERROR,(size_t)0,(dvoid **)0); 
	//申请服务器句柄 
	error_proc(errhp,OCIHandleAlloc((dvoid *)envhp,(dvoid **)&srvhp, 
		OCI_HTYPE_SERVER,(size_t)0,(dvoid **)0)); 
	//申请服务环境句柄 
	error_proc(errhp,OCIHandleAlloc((dvoid *)envhp,(dvoid **)&svchp, 
		OCI_HTYPE_SVCCTX,(size_t)0,(dvoid **)0)); 
	//设置服务环境的服务器属性 
	error_proc(errhp,OCIAttrSet((dvoid *)svchp,OCI_HTYPE_SVCCTX, 
		(dvoid *)srvhp,(ub4)0,OCI_ATTR_SERVER,(OCIError *)errhp)); 
	//连接数据库，建立会话 
	status = OCILogon(envhp,errhp,&svchp,(const OraText*)user,(ub4)strlen((char *)user), 
		(text *)pass_word,(ub4)strlen((char *)pass_word),(text *)servername,(ub4)strlen((char *)servername)); 

	if (status==OCI_SUCCESS) 
		printf("成功连接melinets数据库，已为%s用户建立会话.\n",user); 
	else { 
		printf("连接失败connect fail!\n"); 
		printf("-----ora_search,error in OCIlogon-----\n"); 
		error_proc(errhp,status); 
		return; 
	} 
	//申请语句句柄 
	error_proc(errhp,OCIHandleAlloc((dvoid *)envhp,(dvoid **)&stmthp, 
		OCI_HTYPE_STMT,(size_t)0,(dvoid **)0)); 

	//准备sql语句 
	error_proc(errhp,OCIStmtPrepare(stmthp,errhp,(const OraText*)sqlstat, 
		(ub4)strlen((char *) sqlstat),OCI_NTV_SYNTAX,OCI_DEFAULT)); 

	//-------定义输出变量 
	error_proc(errhp, OCIDefineByPos(stmthp,&defhp[0],errhp,1,&sum, 
		sizeof(sum),SQLT_INT,(sb2 *)0,0,(ub2 *)0,OCI_DEFAULT) ); 

	error_proc(errhp, OCIDefineByPos(stmthp,&defhp[1],errhp,2,&account, 
		sizeof(account),SQLT_STR,(sb2 *)0,0,(ub2 *)0,OCI_DEFAULT) ); 

	// ora_search(&li_ret); 
	// printf("li_ret is %d\n",li_ret); 

	//执行sql语句 
	if ((status=OCIStmtExecute(svchp,stmthp,errhp,(ub4)0, 
		(ub4)0,(const OCISnapshot *)NULL, (OCISnapshot *)NULL, 
		OCI_DEFAULT)) 
		&& status != OCI_SUCCESS_WITH_INFO) 
	{ //失败则退出 
		error_proc(errhp,status); 
		printf("-----ora_search,error in OCIStmtexecute-----\n"); 
		return; 
	} 
	getch(); 

	error_proc(errhp,OCIStmtFetch(stmthp,errhp,1,OCI_FETCH_NEXT,OCI_DEFAULT)); 

	do
	{
		string strValue;
		strValue = account;
		printf("ID:%d  Account:%s\n", sum, strValue.c_str());
		status = OCIStmtFetch(stmthp,errhp,1,OCI_FETCH_NEXT,OCI_DEFAULT);
	}while( OCI_SUCCESS == status );
	//断开连接 
	error_proc(errhp,OCILogoff(svchp,errhp)); 
}