这篇说说如何使用 OCI 示例程序连接及操作数据库。
一、获取数据库连接信息
联系数据库管理员获取数据库连接命令：
psql -h 10.211.55.30 -p 11345 -U tbase -d tdsql
参数说明：
·-h 数据库 IP，通常是 CN 的 IP。
·-p 数据库端口。
·-U 数据库用户。
·-d 需要访问的数据库名称。
二、安装驱动依赖
1. 下载驱动：请单击 TDSQL-PG OCI 驱动包下载。
2. 安装
tar -xvf tdsql_psqloci_tlinux4_x86_64.tar.gz
解压 TDSQL OCI 驱动包，假设解压路径为$PG_OCI_PATH
安装包文件说明：
·include 依赖的头文件，OCI 函数声明。
·lib 依赖库，OCI 函数实现。
·oci_test.c demo，提供参考。
·pg_service.conf 数据库连接信息配置（数据源设置）
·README demo 操作说明
·run.sh demo 执行脚本
3. 配置相关环境信息
3.1 配置连接文件，编辑 pg_service.conf：
[db_test] #数据源名称#数据库服务IPhostaddr=10.211.55.30#数据库服务端口号port=11345#需要连接的数据库dbname=tdsql
注意：OCI 应用程序连接数据库进行 dbname 设置时，使用的是 pg_service.conf 中的数据源名称而不是实际访问的数据库名称。在 OCI 应用程序中配置数据源、用户名和密码。在 pg_service.conf 配置数据库 IP、端口、实际访问的数据库名。
3.2 配置环境变量，编辑 ~/.bashrc。
export LD_LIBRARY_PATH=$PG_OCI_PATH/lib:$LD_LIBRARY_PATHexport PGSERVICEFILE=$PG_OCI_PATH/pg_service.conf
注意：说明：
注意：PGSERVICEFILE：pg_services.conf 文件环境变量，依据实际路径填写。
3.3 环境变量生效
source ~/.bashrc
校验驱动库依赖完整性：
ldd $PG_OCI_PATH/lib/liboci.so
链接不出现 not found 则为成功。
三、编写 OCI 测试程序
示例程序：oci_test.c，已提供在$PG_OCI_PATH路径中，修改用户名、密码、数据源信息即可。
#include "oci.h"#include "oratypes.h"#include "xa.h"#include <unistd.h>#include <stdbool.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <sys/signal.h>#include <unistd.h>#include <pthread.h>#define MAX_SIZE 1024#define MAX_STR_LENTH 256#define MAX_COUNT 3typedef struct __OCI_GLOBAL_CONTEXT_TYPE{ OCIEnv* envhp; OCIServer* srvhp; OCISvcCtx* svchp; OCIError* errhp; OCISession* authp; OCIStmt* stmthp;} OCI_GLOBAL_CONTEXT;//准备阶段测试sword oci_alloc_connect(bool useLogon, OCI_GLOBAL_CONTEXT* ctxptr, char* uname, char* passwd, char* dbname);sword oci_free_disconnect(bool useLogon, OCI_GLOBAL_CONTEXT* ctxptr);void oci_checkerr(OCIError* errhp, sword status);sword oci_exec_sample_sql(OCI_GLOBAL_CONTEXT* ctxptr, char* sql, ub4 mode);sword case0_create(OCI_GLOBAL_CONTEXT *ctxptr);sword case1_select(OCI_GLOBAL_CONTEXT *ctxptr);sword case2_update(OCI_GLOBAL_CONTEXT *ctxptr);sword case3_insert(OCI_GLOBAL_CONTEXT *ctxptr);sword case4_delete(OCI_GLOBAL_CONTEXT *ctxptr);sword case5_vacuum(OCI_GLOBAL_CONTEXT *ctxptr);//根据位置绑定参数和定义结果集测试sword fetch_by_define(void* ptr, char* sql);void test();sword oci_free_handle(OCI_GLOBAL_CONTEXT* ctxptr, char* sql, ub4 mode);sword oci_alloc_handle(OCI_GLOBAL_CONTEXT* ctxptr, char* sql, ub4 mode);/*测试函数：OCIInitialize()、OCIEnvInit()、OCIAttrSet()、OCIStmtPrepare()、OCIStmtExecute()、OCITransCommit()、OCIDescriptorAlloc()、OCIDefineByPos()、OCIStmtFetch()、OCIErrorGet() 1、OCIInitialize()初始化 OCI 应用环境 2、OCIEnvInit()初始化环境句柄 3、OCIDescriptorAlloc()分配句柄 4、OCIAttrSet()设置会话句柄用户名和密码 5、OCIAttrSet()设置环境句柄属性 6、创建并开始一个用户两个会话 7、断开一个会话 8、OCIErrorGet()读取错误信息 9、创建表并执行以下操作 a. OCIStmtPrepare()准备 sql 语句 b. OCIStmtExecute()执行 sql 语句 c. OCITransCommit ()提交事务 d. OCIDefineByPos ()定义输出变量 e. OCIStmtFetch()获取数据 10、结束释放资源，断开数据库连接，释放句柄*//* 需要修改用户名、密码及在 pg_service.conf 中配置的数据源名称，这3个变量均不能为空*/char* uname = "tbase";char* passwd = "1234@abcd";char* dbname = "db_test";int main(int argc, char* argv[]){ test(); return 0;}void test(){ OCI_GLOBAL_CONTEXT ctxptr = {NULL}; sword err = OCI_SUCCESS; do { err = oci_alloc_connect(true, &ctxptr, uname, passwd, dbname); if (err != OCI_SUCCESS) { break; } err = case0_create(&ctxptr); if (err != OCI_SUCCESS) { break; } err = case3_insert(&ctxptr); if (err != OCI_SUCCESS) { break; } err = case1_select(&ctxptr); if (err != OCI_SUCCESS) { break; } oci_alloc_handle(&ctxptr, NULL, OCI_COMMIT_ON_SUCCESS); err = case2_update(&ctxptr); if (err != OCI_SUCCESS) { break; } err = case5_vacuum(&ctxptr); if (err != OCI_SUCCESS) { break; } err = case4_delete(&ctxptr); if (err != OCI_SUCCESS) { break; } oci_free_handle(&ctxptr, NULL, OCI_COMMIT_ON_SUCCESS); oci_free_disconnect(false, &ctxptr); } while (0);}sword case0_create(OCI_GLOBAL_CONTEXT *ctxptr){ char* sql = NULL; sword err = OCI_ERROR; do { // 删除表重建 sql = "drop table if exists case1_bindbypos_define;"; err = oci_exec_sample_sql(ctxptr, sql, OCI_COMMIT_ON_SUCCESS); sql = "create table case1_bindbypos_define(id int, name character varying(255), created character varying(12), attr text);"; err = oci_exec_sample_sql(ctxptr, sql, OCI_COMMIT_ON_SUCCESS); } while (0); return err;}sword case1_select(OCI_GLOBAL_CONTEXT *ctxptr){ char* sql = NULL; sword err = OCI_ERROR; do { //获取结果集 sql = "select * from case1_bindbypos_define where id >10"; err = fetch_by_define((void*)ctxptr, sql); if (err != OCI_SUCCESS) { break; } } while (0); return err;}sword case2_update(OCI_GLOBAL_CONTEXT *ctxptr){ char* sql = NULL; sword err = OCI_ERROR; do { // 更新数据 sql = "update case1_bindbypos_define set name='YYYYYYYYY' where id=100;"; err = oci_exec_sample_sql(ctxptr, sql, OCI_COMMIT_ON_SUCCESS); } while (0); return err;}sword case3_insert(OCI_GLOBAL_CONTEXT *ctxptr){ char* sql = NULL; sword err = OCI_ERROR; do { // 插入数据 sql = "insert into case1_bindbypos_define values(generate_series(1, 10000), 'AAAAAAAAAAAAAAA', 'BBBBBBBBB', 'CCCCCCCCCCCCCC');"; err = oci_exec_sample_sql(ctxptr, sql, OCI_COMMIT_ON_SUCCESS); } while (0); return err;}sword case4_delete(OCI_GLOBAL_CONTEXT *ctxptr){ char* sql = NULL; sword err = OCI_ERROR; do { //删除数据 sql = "delete from case1_bindbypos_define where id < 10001;"; err = oci_exec_sample_sql(ctxptr, sql, OCI_COMMIT_ON_SUCCESS); } while (0); return err;}sword case5_vacuum(OCI_GLOBAL_CONTEXT *ctxptr){ char* sql = NULL; sword err = OCI_ERROR; do { sql = "vacuum full case1_bindbypos_define"; err = oci_exec_sample_sql(ctxptr, sql, OCI_COMMIT_ON_SUCCESS); } while (0); return err;}sword fetch_by_define(void* ptr, char* sql){#define max_one_size 5 sword status = OCI_SUCCESS; OCI_GLOBAL_CONTEXT* ctxptr = (OCI_GLOBAL_CONTEXT*)ptr; OCIDefine* dnfp[4] = {NULL}; int ret = -1; int j = 0; do { int id[max_one_size] = {0}; char name[max_one_size][15] = {{'\\0'}}; char date[max_one_size][12] = {{'\\0'}}; char attr[max_one_size][20] = {{'\\0'}}; // 1 申请执行语句 if (ctxptr->stmthp == NULL) { if ((status = OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->stmthp, (ub4)OCI_HTYPE_STMT, (CONST size_t)0, (dvoid**)0)) != OCI_SUCCESS) { oci_checkerr(ctxptr->errhp, status); break; } } // 3 query sql status = OCIStmtPrepare(ctxptr->stmthp, ctxptr->errhp, (text*)sql, (ub4)strlen((char*)sql), OCI_NTV_SYNTAX, OCI_DEFAULT); if (status != OCI_SUCCESS) { oci_checkerr(ctxptr->errhp, status); break; } //将结果集内存按查询位置绑定到对应列 if (OCIDefineByPos(ctxptr->stmthp, &dnfp[0], ctxptr->errhp, 1, (void*)&id[0], sizeof(int), SQLT_INT, (void*)0, (ub2*)0, (ub2*)0, OCI_DEFAULT) != OCI_SUCCESS) { break; } printf("SUCCESS: OCIDefineByPos ()定义输出变量\\n"); if (OCIDefineByPos(ctxptr->stmthp, &dnfp[1], ctxptr->errhp, 2, (void*)name[0], 15, SQLT_STR, (void*)0, (ub2*)0, (ub2*)0, OCI_DEFAULT) != OCI_SUCCESS) { break; } if (OCIDefineByPos(ctxptr->stmthp, &dnfp[2], ctxptr->errhp, 3, (void*)date[0], 12, SQLT_STR, (void*)0, (ub2*)0, (ub2*)0, OCI_DEFAULT) != OCI_SUCCESS) { break; } if (OCIDefineByPos(ctxptr->stmthp, &dnfp[3], ctxptr->errhp, 4, (void*)attr[0], 20, SQLT_STR, (void*)0, (ub2*)0, (ub2*)0, OCI_DEFAULT) != OCI_SUCCESS) { break; } //因为结果集中的整个列都在一块内存，需要告知分割大小 if (OCIDefineArrayOfStruct(dnfp[0], ctxptr->errhp, sizeof(int), 0, 0, 0) != OCI_SUCCESS) { break; } if (OCIDefineArrayOfStruct(dnfp[1], ctxptr->errhp, 15, 0, 0, 0) != OCI_SUCCESS) { break; } if (OCIDefineArrayOfStruct(dnfp[2], ctxptr->errhp, 12, 0, 0, 0) != OCI_SUCCESS) { break; } if (OCIDefineArrayOfStruct(dnfp[3], ctxptr->errhp, 20, 0, 0, 0) != OCI_SUCCESS) { break; } //SQL执行 status = OCIStmtExecute(ctxptr->svchp, ctxptr->stmthp, ctxptr->errhp, (ub4)max_one_size, (ub4)0, NULL, NULL, OCI_DEFAULT); if (status != OCI_SUCCESS) { oci_checkerr(ctxptr->errhp, status); break; } // fetch data status = OCIStmtFetch(ctxptr->stmthp, ctxptr->errhp, (ub4)max_one_size, (ub4)OCI_FETCH_NEXT, (ub4)OCI_DEFAULT); printf("SUCCESS: OCIStmtFetch()获取数据\\n"); if (status == OCI_SUCCESS) { for (j = 0; j < max_one_size; j++) { printf("%d %d %s %s %s\\n", status, id[j], name[j], date[j], attr[j]); } } else if (status == OCI_NO_DATA) { ub4 ret_val = 0, ret_size = 0; //获取属性值之后会通过循环打印变量值校验 if ((OCIAttrGet((void*)ctxptr->stmthp, (ub4)OCI_HTYPE_STMT, (void*)&ret_val, (ub4*)&ret_size, (ub4)OCI_ATTR_ROW_COUNT, ctxptr->errhp)) != OCI_SUCCESS) { printf("DCIAttrGet fail\\n"); break; } printf("SUCCESS: OCIAttrGet()\\n"); for (j = 0; j < ret_val; j++) { printf("%d %d %s %s %s\\n", status, id[j], name[j], date[j], attr[j]); } } ret = 0; } while (0); //释放stmt句柄 if (ctxptr->stmthp != NULL) { status = OCIHandleFree((dvoid*)ctxptr->stmthp, (ub4)OCI_HTYPE_STMT); if (status != OCI_SUCCESS) { printf("OCIHandleFree OCI_HTYPE_STMT failed\\n"); return OCI_ERROR; } ctxptr->stmthp = NULL; } if (ret == -1) { return OCI_ERROR; } return OCI_SUCCESS;}sword oci_alloc_connect(bool useLogon, OCI_GLOBAL_CONTEXT* ctxptr, char* uname, char* passwd, char* dbname){ sword err = OCI_SUCCESS; do{ //初始化，属于准备过程，无实际运行结果 err = OCIInitialize((ub4)OCI_DEFAULT, (dvoid*)0, (dvoid * (*)(dvoid*, size_t))0, (dvoid * (*)(dvoid*, dvoid*, size_t))0, (void (*)(dvoid*, dvoid*))0); if (err != OCI_SUCCESS) { printf("FAILED: OCIInitialize()\\n"); break; } printf("SUCCESS: OCIInitialize()初始化OCI应用环境\\n"); //申请env句柄，属于准备过程，无实际运行结果 err = OCIEnvInit((OCIEnv**)&ctxptr->envhp, OCI_DEFAULT, 0, NULL); if (err != OCI_SUCCESS) { printf("FAILED: OCIEnvInit()\\n"); break; } printf("SUCCESS: OCIEnvInit()初始化环境句柄\\n"); //申请错误句柄，属于准备过程，无实际运行结果 if (OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->errhp, (ub4)OCI_HTYPE_ERROR, (size_t)0, (dvoid**)0)) { printf("FAILED: OCIHandleAlloc() on ctxptr->errhp\\n"); break; } //申请 srv 句柄，属于准备过程，无实际运行结果 if (OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->srvhp, (ub4)OCI_HTYPE_SERVER, (size_t)0, (dvoid**)0)) { printf("FAILED: OCIHandleAlloc() on ctxptr->srvhp\\n"); break; } //申请 svch 句柄，属于准备过程，无实际运行结果 if (OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->svchp, (ub4)OCI_HTYPE_SVCCTX, (size_t)0, (dvoid**)0)) { printf("FAILED: OCIHandleAlloc() on ctxptr->svchp\\n"); break; } //申请 auth 句柄，属于准备过程，无实际运行结果 if (OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->authp, (ub4)OCI_HTYPE_SESSION, (size_t)0, (dvoid**)0)) { printf("FAILED: OCIHandleAlloc() on ctxptr->authp\\n"); break; } printf("SUCCESS: OCIHandleAlloc()分配句柄\\n"); //申请执行语句 if (OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->stmthp, (ub4)OCI_HTYPE_STMT, (CONST size_t)0, (dvoid**)0)) { printf("FAILED: OCIHandleAlloc() on ctxptr->stmthp\\n"); break; } //非测试接口，属于辅助接口 if (OCIServerAttach(ctxptr->srvhp, ctxptr->errhp, (text*)dbname, (sb4)strlen((char*)dbname), (ub4)OCI_DEFAULT)) { printf("FAILED: OCIServerAttach()\\n"); break; } //将 srvh 属性设置到 svch 句柄，属于准备过程，无实际运行结果 if (OCIAttrSet((dvoid*)ctxptr->svchp, (ub4)OCI_HTYPE_SVCCTX, (dvoid*)ctxptr->srvhp, (ub4)0, (ub4)OCI_ATTR_SERVER, ctxptr->errhp)) { printf("FAILED: OCIAttrSet() server attribute\\n"); break; } printf("SUCCESS: OCIAttrSet()设置环境句柄属性\\n"); //注意，OCIHandleAlloc申请其他句柄过程中已经将其保存到环境句柄，OCIAttrSet将srvhp句柄属性保存到svchp过程相当于也同时保存到env //将 uname 设置到 auth 句柄，属于准备过程，无实际运行结果 if (OCIAttrSet((dvoid*)ctxptr->authp, (ub4)OCI_HTYPE_SESSION, (dvoid*)uname, (ub4)strlen((char*)uname), (ub4)OCI_ATTR_USERNAME, ctxptr->errhp)) { printf("FAILED: OCIAttrSet() userid\\n"); break; } printf("SUCCESS: OCIAttrSet()设置会话句柄用户名\\n"); //将 passwd 设置到 auth 句柄，属于准备过程，无实际运行结果 if (OCIAttrSet((dvoid*)ctxptr->authp, (ub4)OCI_HTYPE_SESSION, (dvoid*)passwd, (ub4)strlen((char*)passwd), (ub4)OCI_ATTR_PASSWORD, ctxptr->errhp)) { printf("FAILED: OCIAttrSet() passwd\\n"); break; } printf("SUCCESS: OCIAttrSet()设置会话句柄密码\\n"); //开启一个会话，后续代码中有数据库操作，可以证明该接口生效 if (OCISessionBegin((dvoid*)ctxptr->svchp, ctxptr->errhp, ctxptr->authp, (ub4)OCI_CRED_RDBMS, (ub4)OCI_DEFAULT)) { text sqlstate[6] = "", msg[256] = ""; sb4 errcode = 0; OCIErrorGet(ctxptr->errhp, 1, sqlstate, &errcode, msg, 256, OCI_HTYPE_ERROR); printf("SUCCESS: OCIErrorGet()读取错误信息\\n"); printf("initialize failed: %d %s\\n", errcode, msg); break; } printf("SUCCESS: 创建并开始一个用户会话\\n"); //将 auth 设置到 svchp 句柄，属于准备过程，无实际运行结果 if (OCIAttrSet((dvoid*)ctxptr->svchp, (ub4)OCI_HTYPE_SVCCTX, (dvoid*)ctxptr->authp, (ub4)0, (ub4)OCI_ATTR_SESSION, ctxptr->errhp)) { printf("FAILED: OCIAttrSet() session\\n"); break; } return OCI_SUCCESS; } while (0); return OCI_ERROR;}void oci_checkerr(OCIError* errhp, sword status){ text errbuf[512] = {'\\0'}; sb4 errcode; if (status == OCI_SUCCESS) { return; } switch (status) { case OCI_SUCCESS_WITH_INFO: { printf("Error – OCI_SUCCESS_WITH_INFO\\n"); OCIErrorGet((void*)errhp, (ub4)1, (text*)NULL, &errcode, errbuf, (ub4)sizeof(errbuf), (ub4)OCI_HTYPE_ERROR); printf("Error %d – %s\\n", errcode, errbuf); break; } case OCI_NEED_DATA: { printf("Error – OCI_NEED_DATA\\n"); break; } case OCI_NO_DATA: { printf("Error – OCI_NO_DATA\\n"); break; } case OCI_ERROR: { OCIErrorGet((void*)errhp, (ub4)1, (text*)NULL, &errcode, errbuf, (ub4)sizeof(errbuf), (ub4)OCI_HTYPE_ERROR); printf("OCI_ERROR %d – %s\\n", errcode, errbuf); break; } case OCI_INVALID_HANDLE: { printf("Error – OCI_INVALID_HANDLE\\n"); break; } case OCI_STILL_EXECUTING: { printf("Error – OCI_STILL_EXECUTING\\n"); break; } case OCI_CONTINUE: { printf("Error – OCI_CONTINUE\\n"); break; } default: { printf("Error – %d\\n", status); break; } }}//退出，并释放对应的句柄资源sword oci_free_disconnect(bool useLogon, OCI_GLOBAL_CONTEXT* ctxptr){ sword err = OCI_SUCCESS; printf("SUCCESS: 结束释放资源，断开数据库连接，释放句柄\\n"); //结束会话 err = OCILogoff(ctxptr->svchp, ctxptr->errhp); if (err != OCI_SUCCESS) { printf("FAILED: OCILogoff()\\n"); } //句柄释放 if (ctxptr->svchp != NULL) { err = OCIHandleFree((dvoid*)ctxptr->svchp, (ub4)OCI_HTYPE_SVCCTX); if (err != OCI_SUCCESS) { printf("FAILED: OCIHandleFree() on ctxptr->svchp\\n"); } ctxptr->svchp = NULL; } if (ctxptr->errhp) { err = OCIHandleFree((dvoid*)ctxptr->errhp, (ub4)OCI_HTYPE_ERROR); ctxptr->errhp = NULL; } if (ctxptr->envhp) { err = OCIHandleFree((dvoid*)ctxptr->envhp, (ub4)OCI_HTYPE_ENV); ctxptr->envhp = NULL; } return err;}sword oci_exec_sample_sql(OCI_GLOBAL_CONTEXT* ctxptr, char* sql, ub4 mode){ sword err = OCI_SUCCESS; bool new_stmt = false; do { //SQL 准备，无实际运行结果 err = OCIStmtPrepare(ctxptr->stmthp, ctxptr->errhp, (const text*)sql, (ub4)strlen((char*)sql), (ub4)OCI_NTV_SYNTAX, (ub4)OCI_DEFAULT); if (err != OCI_SUCCESS) { text sqlstate[6] = "", msg[256] = ""; sb4 errcode = 0; OCIErrorGet(ctxptr->errhp, 1, sqlstate, &errcode, msg, 256, OCI_HTYPE_ERROR); printf("OCIStmtPrepare failed: %d %s\\n", errcode, msg); break; } //SQL 执行，并未提交，需要执行 OCITransCommit 后方可验证 err = OCIStmtExecute(ctxptr->svchp, ctxptr->stmthp, ctxptr->errhp, 1, 0, (OCISnapshot*)0, (OCISnapshot*)0, mode); if (err != OCI_SUCCESS) { text sqlstate[6] = "", msg[256] = ""; sb4 errcode = 0; OCIErrorGet(ctxptr->errhp, 1, sqlstate, &errcode, msg, 256, OCI_HTYPE_ERROR); printf("OCIStmtExecute failed: %d %s\\n", errcode, msg); break; } //提交 //具体，SQL 命令执行：\\d case1_bindbypos_define，可查看表已经存在 if (mode == OCI_DEFAULT) { err = OCITransCommit(ctxptr->svchp, ctxptr->errhp, (ub4)OCI_DEFAULT); if (err != OCI_SUCCESS) { printf("OCITransCommit failed\\n"); break; } } } while (0); if (new_stmt && ctxptr->stmthp != NULL) { //释放句柄，无实际运行结果 err = OCIHandleFree((dvoid*)ctxptr->stmthp, (ub4)OCI_HTYPE_STMT); if (err != OCI_SUCCESS) { printf("OCIHandleFree failed\\n"); } ctxptr->stmthp = NULL; } return err;}sword oci_alloc_handle(OCI_GLOBAL_CONTEXT* ctxptr, char* sql, ub4 mode){ sword err = OCI_SUCCESS; bool new_stmt = false; do { //申请执行语句 if (ctxptr->stmthp == NULL) { if (OCIHandleAlloc((dvoid*)ctxptr->envhp, (dvoid**)&ctxptr->stmthp, (ub4)OCI_HTYPE_STMT, (CONST size_t)0, (dvoid**)0)) { printf("FAILED: alloc statement handle\\n"); break; } else { new_stmt = true; } } } while (0); return err;}sword oci_free_handle(OCI_GLOBAL_CONTEXT* ctxptr, char* sql, ub4 mode){ sword err = OCI_SUCCESS; if ( ctxptr->stmthp != NULL) { //释放句柄，无实际运行结果 err = OCIHandleFree((dvoid*)ctxptr->stmthp, (ub4)OCI_HTYPE_STMT); if (err != OCI_SUCCESS) { printf("OCIHandleFree failed\\n"); } ctxptr->stmthp = NULL; } return err;}
1. 修改示例代码中 uname、passwd、dbname 三个变量为用户名、密码、在 pg_service.conf 中配置的数据源名称（username,password,db_name）。
2. 运行：
cd $PG_OCI_PATH./run.sh
结果：
SUCCESS: OCIInitialize()初始化OCI应用环境SUCCESS: OCIEnvInit()初始化环境句柄SUCCESS: OCIHandleAlloc()分配句柄SUCCESS: OCIAttrSet()设置环境句柄属性SUCCESS: OCIAttrSet()设置会话句柄用户名SUCCESS: OCIAttrSet()设置会话句柄密码SUCCESS: 创建并开始一个用户会话SUCCESS: OCIDefineByPos ()定义输出变量SUCCESS: OCIStmtFetch()获取数据0 11 AAAAAAAAAAAAAA BBBBBBBBB CCCCCCCCCCCCCC0 12 AAAAAAAAAAAAAA BBBBBBBBB CCCCCCCCCCCCCC0 13 AAAAAAAAAAAAAA BBBBBBBBB CCCCCCCCCCCCCC0 14 AAAAAAAAAAAAAA BBBBBBBBB CCCCCCCCCCCCCC0 15 AAAAAAAAAAAAAA BBBBBBBBB CCCCCCCCCCCCCCSUCCESS: 结束释放资源，断开数据库连接，释放句柄