sqlite3 读写二进制数据

转载：http://blog.csdn.net/chence19871/article/details/7645934

#include <stdio.h>#include <windows.h>#include <iostream>using namespace std;extern "C"{#include "./sqlite3.h"};void sqlite3_exec_report(sqlite3* db, const char* sql, sqlite3_callback func_callback, void *para);void select_v2(sqlite3 *db, const char*sql);void outputItem(sqlite3_stmt* stat, int nColumn, char* out_pic_path);string GetType(int t);//回调函数int select_items(void *para, int n_column, char **column_val, char **column_name);//查询int main(int args, char*argv[]){int result, ret;sqlite3* db = NULL;char* errmsg = NULL;char module_path[100];//获取当前exe路径DWORD dwPathLen = GetModuleFileNameA(NULL, module_path, 100);char *p = module_path + dwPathLen;while (1){char c = *p;if (c == '\\'){*(p+1) = '\0';break;}p--;}//合成数据库文件路径strcat_s(module_path, 100, "db\\mydb.db");string db_path(module_path);//打开(创建)数据库result = sqlite3_open(db_path.c_str(), &db);//----------------------------第一张表------------------------------//--不包含blob数据，通过普通的方法插入//-- --------------------------------------------------------------if (result == SQLITE_OK){//创建第一张表sqlite3_exec_report(db, "create table MyTable_1(ID integer autoincrement primary key, name nvarchar(30)）", NULL, NULL);//先清除数据sqlite3_exec_report(db, "delete from MyTable_1", NULL, NULL);//插入数据const char * sqls[] = {"insert into MyTable_1(ID,name) values(0, '钱学森')","insert into MyTable_1(ID,name) values(1, '邓稼先')","insert into MyTable_1(ID,name) values(2, '钱三强')","insert into MyTable_1(ID,name) values(3, '李四光')","insert into MyTable_1(ID,name) values(4, '贺才良')"};for (int i = 0; i < sizeof(sqls)/sizeof(char*); i++){sqlite3_exec_report(db, sqls[i], NULL, NULL);}//查询插入的数据  用的是回调的方法sqlite3_exec_report(db, "select * from MyTable_1", select_items, NULL);sqlite3_close(db);}else{//打开数据库失败cout << sqlite3_errmsg(db) << endl;ret = -1;}//-----------------------------第二张表------------------------------//--包含blob数据，通过sqlite3_prepare，sqlite3_bind_blob，sqlite3_step//-- 的方法实现数据的插入//-- --------------------------------------------------------------result = sqlite3_open(module_path, &db);if (result==SQLITE_OK){sqlite3_exec_report(db, "create table stu_msg(ID integer primary key autoincrement, name nvarchar(32), picture blob)", NULL, NULL);sqlite3_exec_report(db, "delete from stu_msg", NULL, NULL);sqlite3_stmt *stat;const char *pzTail = NULL;const char *sqls[] = {"insert into stu_msg(ID, name, picture) values(0, '华罗庚', ?);","insert into stu_msg(ID, name, picture) values(1, '钱学森', ?);"};const char *names[] = {"pic\\hualuogen.jpg","pic\\qianxuesen.jpg"};for (int j=0; j<sizeof(sqls)/sizeof(char*); j++){//准备result = sqlite3_prepare(db, sqls[j], -1, &stat, &pzTail);if (!result && stat){// 读取头像数据*(p+1) = '\0';//重复利用ModuleFileNamestrcat_s(module_path, 100, names[j]);FILE *file = NULL;fopen_s(&file, module_path, "rb+");char* data = NULL;long l_file_size = 0;if (file){fseek(file, 0, SEEK_END);l_file_size = ftell(file);fseek(file, 0, SEEK_SET);data = new char[l_file_size];fread(data, 1, l_file_size, file);//和sql的第一个？绑定（如果有多个问号，那就要分开绑定）result = sqlite3_bind_blob(stat, 1, data, l_file_size, NULL);//将数据输入数据库result = sqlite3_step(stat);cout << "Insert result:" << sqlite3_errmsg(db) << endl;fclose(file);delete [] data;}ret = 0;}else{//准备失败cout << "sqlite3_prepare failed!  " << sqlite3_errmsg(db) << endl;ret = -1;}//释放statsqlite3_finalize(stat);}//查看插入数据select_v2(db, "select ID, name, picture from stu_msg");//关闭数据库sqlite3_close(db);}else{cout << "打开数据库" << module_path << sqlite3_errmsg(db);ret = -1;}//---------------------读出各记录的头像-----------------result = sqlite3_open(db_path.c_str(), &db);if (!result){sqlite3_stmt *stat;const char *pzTail = NULL;sqlite3_prepare(db, "select * from stu_msg;", -1, &stat, &pzTail);int nColumn = sqlite3_column_count(stat);cout << "总的列数:" << nColumn << endl;result = sqlite3_step(stat);//读取某一条记录while (result == SQLITE_ROW) /* sqlite3_step() has another row ready */{*(p+1) = '\0';outputItem(stat, nColumn, module_path);cout << endl;result = sqlite3_step(stat);}cout << "end..." << endl;}return ret;}//输出一条记录void outputItem(sqlite3_stmt* stat, int nColumn, char* out_pic_path){int m = -1;for (int k=0; k< nColumn; k++){string s;int colType = sqlite3_column_type(stat, k);if (colType == 3)//text{m = k; //得到名字}s = GetType(colType);cout << "column " << k << ":" << s.c_str() << endl;switch(colType){case 1: cout << "Value: " << sqlite3_column_int(stat, k) << endl;break;case 2: cout << "Value: " << sqlite3_column_int(stat, k) << endl; break;case 3: cout << "Value: " << sqlite3_column_text(stat, k) << endl; break;case 5: cout << "Value: " << "内容为空" << endl; break;case 4: cout << "Value: " << "二进制数据" << endl;const void* bi = sqlite3_column_blob(stat, k);int size = sqlite3_column_bytes(stat,k);char *name = NULL;if (m == -1){name = "xxx";}else{name = (char*)sqlite3_column_text(stat, m);}strcat_s(out_pic_path, 100, "out_pic\\");strcat_s(out_pic_path, 100, (char*)name);strcat_s(out_pic_path, 100, ".jpg");FILE *f = NULL;fopen_s(&f, out_pic_path, "wb+");if (f){fwrite(bi, 1, size, f);fclose(f);}break;}}}//获取类型string GetType(int t){string s;switch (t){case 1: s = "SQLITE_INTEGER";break;case 2: s = "SQLITE_FLOATE"; break;case 3: s = "SQLITE_TEXT"; break;case 4: s = "SQLITE_BLOB"; break;case 5: s = "SQLITE_NULL"; break;}return s;}//执行sql语句并报告执行结果void sqlite3_exec_report(sqlite3* db, const char* sql, sqlite3_callback func_callback, void *para){char* errmsg;int result = sqlite3_exec(db, sql, func_callback, para, &errmsg);cout << endl << endl;if(result != SQLITE_OK){cout << "error code： " << result << endl<< "error： " << errmsg << endl;}elsecout << "SQL execute succeed: " << sql << endl;}//一条记录调用一次回调函数int select_items(void *para, int n_column, char **column_val, char **column_name){int i;cout << "contain " << n_column << " columns" << endl;for (i = 0; i<n_column; i++){cout << "column" << i << ": " << column_name[i] << endl<< "values: " << column_val[i] << endl;}return 0;}//另一种查询方式void select_v2(sqlite3 *db, const char*sql){#if 1char *errmsg = NULL;char** dbResult = NULL;int nRow, nColumn;int result = sqlite3_get_table( db, sql, &dbResult, &nRow, &nColumn, &errmsg );//查询成功int index = nColumn; //dbResult 前面第一行数据是字段名称，从 nColumn 索引开始才是真正的数据for( int i = 0; i < nRow ; i++ ){cout << "第" << i+1 << "条记录" << endl;for(int j = 0 ; j < nColumn; j++ ){cout << "字段名：" << dbResult[j] << "  "<< "字段值：" << dbResult[index] << endl;++index; // dbResult 的字段值是连续的，从第0索引到第 nColumn - 1索引都是字段名称，从第 nColumn 索引开始，后面都是字段值，它把一个二维的表（传统的行列表示法）用一个扁平的形式来表示}cout << "------------" << endl;}sqlite3_free_table(dbResult);//释放查询空间#endif}