项目中需要使用的sqllite,有想过使用内存的结果,好像都不大使用,最接近的算是vector了,但是查询方式不大好,而且数据有好几个字段,所以考虑了数据库
sqllite目前已经到了3了,好快,好像这个数据库也不弱!就先用着吧!
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其实挺简单的,主要也就是一个class
main函数里面有对应的测试函数
暂时没有发现bug,如果出现,请务必提醒本人!谢啦!
详情请看main函数
测试项目的链接:
http://download.csdn.net/detail/zengraoli/7457843
sql_lite_helper.h:
#ifndef __INCLUDE_SQL_LITE_HELPER_H__
#define __INCLUDE_SQL_LITE_HELPER_H__
#include "sqlite3.h"
#pragma comment(lib, "sqlite3.lib")
class SQLiteHelper
{
public:
SQLiteHelper() { }
virtual ~SQLiteHelper() { CloseDB(); }
// 打开数据库
int OpenDB(const char *path);
// 关闭数据库
int CloseDB();
// 创建一张表
int CreateTable(const char *create_table_state);
// 删除一张表
int DropTable(const char *table_name);
// 查询操作
int Select(const char *select_state);
// 插入操作
int Insert(const char *insert_state);
// 删除操作
int Delete(const char *delete_state);
// 更新操作
int Update(const char *update_state);
private:
sqlite3 *sqlite_db_;// 数据库的指针
char* err_msg_; // 错误信息
bool is_close_; // 关闭数据的标识
// 主要用在selece操作中的显示数据元素
static int CallBackFunc(void *NotUsed, int argc, char **argv, char **azColName);
// 执行sql语句
int SqlStateExec(const char *sql_state);
};
#endifsql_lite_helper.cpp:
#include "iostream"
using namespace std;
#include "sql_lite_helper.h"
int SQLiteHelper::OpenDB(const char *path)
{
int res = sqlite3_open(path, &sqlite_db_);
if(res)
{
cout << "can't open database: " << sqlite3_errmsg(sqlite_db_);
sqlite3_close(sqlite_db_);
return -1;
}
is_close_ = false;
return 0;
}
int SQLiteHelper::CloseDB()
{
if (!is_close_)
{
int res = sqlite3_close(sqlite_db_);
if(res)
{
cout << "can't close database: " << sqlite3_errmsg(sqlite_db_);
return -1;
}
}
return 0;
}
int SQLiteHelper::CreateTable(const char *table_name_and_field)
{
string create_table_state = "create table ";
create_table_state += table_name_and_field;
create_table_state += ";";
int res = SqlStateExec(create_table_state.c_str());
if (res != SQLITE_OK)
{
cout << "create table failed." << err_msg_ << endl;
return -1;
}
else
{
cout << "create table successed." << endl;
}
return 0;
}
int SQLiteHelper::DropTable(const char *table_name)
{
string sql_state = "drop table ";
sql_state += table_name;
sql_state += ";";
int res = SqlStateExec(sql_state.c_str());
if (res != SQLITE_OK)
{
cout << "drop table failed." << err_msg_ << endl;
return -1;
}
else
{
cout << "drop table successed." << endl;
}
return 0;
}
int SQLiteHelper::Select(const char *select_state)
{
int res = SqlStateExec(select_state);
if (res != SQLITE_OK)
{
cout << "select operate failed." << err_msg_ << endl;
return -1;
}
else
{
cout << "select operate successed." << endl;
}
return 0;
}
int SQLiteHelper::Insert(const char *insert_state)
{
int res = sqlite3_exec(sqlite_db_, "begin transaction;", CallBackFunc, 0, &err_msg_);
res = SqlStateExec(insert_state);
if (res != SQLITE_OK)
{
cout << "insert operate failed." << err_msg_ << endl;
return -1;
}
res = sqlite3_exec(sqlite_db_, "commit transaction;", 0, 0, &err_msg_);
cout << "insert operate successed." << endl;
return 0;
}
int SQLiteHelper::Delete(const char *delete_state)
{
int res = SqlStateExec(delete_state);
if (res != SQLITE_OK)
{
cout << "delete operate failed." << err_msg_ << endl;
return -1;
}
else
{
cout << "delete operate successed." << endl;
}
return 0;
}
int SQLiteHelper::Update(const char *update_state)
{
int res = SqlStateExec(update_state);
if (res != SQLITE_OK)
{
cout << "update operate failed." << err_msg_ << endl;
return -1;
}
else
{
cout << "update operate successed." << endl;
}
return 0;
}
int SQLiteHelper::CallBackFunc(void *not_used, int element_count, char **element, char **col_name)
{
for(int index = 0 ; index < element_count ; index++)
{
cout << col_name[index] << " = " << (element[index] ? element[index] : "NULL") << ", ";
}
cout << "\n";
return 0;
}
int SQLiteHelper::SqlStateExec(const char *sql_state)
{
return sqlite3_exec(sqlite_db_, sql_state, CallBackFunc, 0, &err_msg_);
}main:
// test_use_sqlite.cpp : 定义控制台应用程序的入口点。
//
#include "stdafx.h"
#include "iostream"
#include "sstream"
using namespace std;
#include "sql_lite_helper.h"
SQLiteHelper sql_lite_helper;
// Test:创建一个数据库表
int TestCreateTable()
{
return sql_lite_helper.CreateTable("test_table (id int, name varchar, age int)");
}
// Test:测试插入数据
int TestInsert()
{
for (int i= 1; i < 10; ++i)
{
std::stringstream str_sql;
str_sql << "insert into test_table values(";
str_sql << i << ","<< (i + 10) << "," << 23 << ");";
std::string str = str_sql.str();
sql_lite_helper.Insert(str.c_str());
}
return 0;
}
// Test:测试删除某个元素
int TestDelete()
{
string str_sql= "delete from test_table where id=4;";
return sql_lite_helper.Delete(str_sql.c_str());
}
// Test:测试更新某个元素
int TestUpdate()
{
string str_sql= "update test_table set name='SQLite3' where name='17';";
return sql_lite_helper.Update(str_sql.c_str());
}
// Test:测试查询
int TestSelect()
{
string str_sql= "select * from test_table;";
return sql_lite_helper.Select(str_sql.c_str());
}
// Test:测试删除表
int TestDropTable()
{
return sql_lite_helper.DropTable("test_table");
}
int main()
{
int res = sql_lite_helper.OpenDB("./Test.db3");
res = TestCreateTable();
if (res != 0)
{
return 0;
}
res = TestInsert();
if (res != 0)
{
return 0;
}
TestSelect();
res = TestDelete();
if (res != 0)
{
return 0;
}
res = TestUpdate();
if (res != 0)
{
return 0;
}
TestSelect();
TestDropTable();
TestSelect();
return 0;
}显示结果:
原文:http://blog.csdn.net/zengraoli/article/details/28896617