sqlite3学习

//

//  main.cpp

//  sqlite

//

//  Created by yuer on 14-9-13.

//  Copyright (c) 2014年 yuer. All rights reserved.

//

 

#include <iostream>

#include <stdio.h>

#include <stdlib.h>

using namespace std;

#include "sql/sqlite3.h"

 

int loadMyInfo(void * param, int column, char** columnValue, char** columnName);

 

int main(int argc, const char * argv[])

{

    sqlite3*    hSqlite = nullptr;

    char*       errmsg  = nullptr;// 错误信息

    

    // 打开数据库，没有则创建test.db

    int ret = sqlite3_open("test.db", &hSqlite);

    if (ret != SQLITE_OK)

    {

        cout<<"Open sqlite is failed!"<<endl;

    }

    

    // 删除表

    ret = sqlite3_exec(hSqlite, "DROP table mytables;", nullptr, nullptr, &errmsg);

    if (ret != SQLITE_OK)

    {

        printf("err: %s ", errmsg);

    }

    

    // 创建表

    ret = sqlite3_exec(hSqlite, "create table mytables (id integer primary key, value text, name text);", nullptr, nullptr, &errmsg);

    if (ret != SQLITE_OK)

    {

        printf("err: %s ", errmsg);

    }

    

    // 插入数据

    ret = sqlite3_exec(hSqlite,"insert into mytables values(1, 'des1', 'name1');", nullptr,

                 nullptr, &errmsg);

    if (ret != SQLITE_OK)

    {

        printf("err: %s ", errmsg);

    }

    ret = sqlite3_exec(hSqlite,"insert into mytables values(2, 'des2', 'name2');", nullptr,

                       nullptr, &errmsg);

    if (ret != SQLITE_OK)

    {

        printf("err: %s ", errmsg);

    }

    ret = sqlite3_exec(hSqlite,"insert into mytables values(3, 'des3', 'name3');", nullptr,

                       nullptr, &errmsg);

    if (ret != SQLITE_OK)

    {

        printf("err: %s ", errmsg);

    }

    

    // 二进制写入

    sqlite3_stmt* write;

    sqlite3_prepare_v2(hSqlite, "insert into ? values(18, 'test', 'test');", -1, &write, 0);

    std::string value = "10";

    std::string dbName = "mytables";

    sqlite3_bind_blob(write, 1, dbName.c_str(), -1, SQLITE_TRANSIENT);// 绑定数据

    //sqlite3_bind_int(write, 1, 6);

    //sqlite3_bind_text(write, 2, value.c_str(), -1, SQLITE_TRANSIENT);// 绑定数据

    //sqlite3_bind_blob(write, 3, value.c_str(), -1, SQLITE_TRANSIENT);// 绑定数据

    sqlite3_step(write);            // 执行

    sqlite3_reset(write);

    sqlite3_finalize(write);        // 释放

    

    // 读出二进制

    sqlite3_stmt* read;

    sqlite3_prepare(hSqlite, "select * from mytables", -1, &read, 0);

    printf("----二进制查询结果--- ");

    while (sqlite3_step(read) == SQLITE_ROW)

    {

        int id = sqlite3_column_int(read, 0);

        const void * pText = sqlite3_column_blob(read, 1);

        int len = sqlite3_column_bytes(read, 1);

        std::string text((char*)pText, len);

        const void * pName = sqlite3_column_blob(read, 2);

        int nameLen = sqlite3_column_bytes(read, 2);

        std::string name((char*)pName, nameLen);

        printf("%d-%s-%s ", id, text.c_str(), name.c_str());

    }

    sqlite3_finalize(read);

    printf("----二进制查询结果--- ");

    

    

    // 查询数据

    ret = sqlite3_exec(hSqlite,"select * from mytables;", loadMyInfo,

                       (void*)"param", &errmsg);

    if (ret != SQLITE_OK)

    {

        printf("err: %s ", errmsg);

    }

    

    // 不使用回调的查询

    char** dbResult;

    int row, column;

    ret = sqlite3_get_table(hSqlite, "select * from mytables;", &dbResult, &row, &column, &errmsg);

    if (ret == SQLITE_OK)

    {

        printf("----<>----- ");

        printf("查到%d条结果 ", row);

        int index = column;

        for (int i = 0; i< row; i++)

        {

            for (int j = 0; j< column; j++)

            {

                printf("[%s]:%s, ", dbResult[j], dbResult[index++]);

            }

            printf(" ");

        }

        printf("----<>----- ");

    }

    sqlite3_free_table(dbResult);// 释放查询结果

    sqlite3_errcode(hSqlite);

    // 关闭数据库

    sqlite3_close(hSqlite);

    return 0;

}

 

 

// 每查到一条结果就调用一次

int loadMyInfo(void * param, int column, char** columnValue, char** columnName)

{

    printf("param: %s ", (char*)param);

    printf("********** ");

 

    for (int i = 0; i< column; i++)

    {

        printf("[%s]：%s,", columnName[i], columnValue[i]);

    }

    printf(" ********** ");

    return 0;

}