SQLlite使用、创建、插入、修改、查询

/**
 *  导入类库libsqlite3.0.dylib
 *  头文件sqlite3.h
 *  创建数据库
 */
+ (BOOL)createSqlite
{
    //1、打开数据库，获取存放路径
    NSString *path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingString:@"/user.sqlite"];
    
    //创建数据库返回值是init类型
    /*
     const char *filename,   Database filename (UTF-8)
    sqlite3 **ppDb            OUT: SQLite db handle
     */
    //打开数据库所在的内存地址
    sqlite3 *sqlite =NULL;
    
    //如果文件存在不会重新创建，不存在就创建新的文件
    int isSuccess = sqlite3_open([path UTF8String], &sqlite);
    //判断是否创建成功
    if (isSuccess != SQLITE_OK) {
        NSLog(@"打开数据库失败");
        return NO;
    }
    
    //2、sql语句执行
    /*
    sqlite3*,                                  An open database
    const char *sql,                           SQL to be evaluated
    int (*callback)(void*,int,char**,char**),  Callback function
    void *,                                    1st argument to callback
    char **errmsg                              Error msg written here
    */
    NSString *sql = @"create table if not exists user_info(user_name text, user_id text , user_age int)";
    char *error = nil;
    int result = sqlite3_exec(sqlite, [sql UTF8String], nil, nil, &error);
    
    //判断执行是否成功
    if (result != SQLITE_OK) {
        NSLog(@"执行创建表语句失败");
        
        //执行失败关闭数据库
        sqlite3_close(sqlite);
        
        return NO;
    }
    
    //3、关闭数据库
    sqlite3_close(sqlite);
    
    return YES;
}

/**
 *  插入数据
 */
+ (BOOL)insertSqliteWithDataModal:(UserModal *)modal;
{
    //1、打开数据库，获取存放路径
    NSString *path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingString:@"/user.sqlite"];
    
    //创建数据库返回值是init类型
    //打开数据库所在的内存地址
    sqlite3 *sqlite =NULL;
    
    int result = sqlite3_open([path UTF8String], &sqlite);
    //判断是否创建成功
    if (result != SQLITE_OK) {
        NSLog(@"创建数据库失败");
        return NO;
    }
    //创建句柄
    sqlite3_stmt *stmt = nil;
    
    //2、创建sql,插入的数据是在外界传入的，使用？占位符，使用句柄将外界传入的数据，和对应的占位符关联
    NSString *sqlStr = @"insert into user_info(user_name, user_id, user_age) values(?,?,?)";
    
    //3、sql编译将写好的sql语句和句柄关联
    result = sqlite3_prepare(sqlite , [sqlStr UTF8String], -1, &stmt, NULL);
    if (result != SQLITE_OK) {
        NSLog(@"SQL语句编译失败");
        //关闭数据库和句柄
        sqlite3_close(sqlite);
        sqlite3_finalize(stmt);
        return NO;
    }
    
    //4、获取modal中的数据
    NSString *name = modal.userName;
    NSString *ID = modal.userID;
    NSInteger age = modal.userAge;
    //通过句柄向sql语句中的占位符填充数据
    /**
     *  @param stmt   句柄
     *  @param 1      在sql语句中的位置
     *  @param          要填充的内容
     *  @param          写入的字符块的大小 -1没有限制
     *  @param
     */
    sqlite3_bind_text(stmt, 1, [name UTF8String], -1, NULL);
    sqlite3_bind_text(stmt, 2, [ID UTF8String], -1, NULL);
    sqlite3_bind_int64(stmt, 3, age);
    
    //5、执行sql语句
    result = sqlite3_step(stmt);
    
    if (result != SQLITE_DONE) {
        NSLog(@"执行语句失败");
        
        //关闭数据库和句柄
        sqlite3_close(sqlite);
        sqlite3_finalize(stmt);
        return NO;
    }
    
    //6、关闭数据库和句柄
    sqlite3_close(sqlite);
    sqlite3_finalize(stmt);
    
    return YES;
}

/**
 *  修改数据
 */
+ (BOOL)updateData
{
    //1、打开数据库，获取存放路径
    NSString *path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingString:@"/user.sqlite"];
    
    //创建数据库返回值是init类型
    //打开数据库所在的内存地址
    sqlite3 *sqlite =NULL;
    
    int result = sqlite3_open([path UTF8String], &sqlite);
    //判断是否创建成功
    if (result != SQLITE_OK) {
        NSLog(@"打开数据库失败");
        return NO;
    }
    //创建句柄
    sqlite3_stmt *stmt = nil;
    
    //2、创建sql语句
    NSString *sqlStr = @"update user_info set user_name = ? where user_id = ?";
    
    //编译sql
    result = sqlite3_prepare(sqlite , [sqlStr UTF8String], -1, &stmt, NULL);
    if (result != SQLITE_OK) {
        NSLog(@"SQL语句编译失败");
        //关闭数据库和句柄
        sqlite3_close(sqlite);
        sqlite3_finalize(stmt);
        return NO;
    }
    
    //3、//通过句柄向sql语句中的占位符填充数据
    NSString *name = @"Tom";
    NSString *ID = @"1088";
    sqlite3_bind_text(stmt, 1, [name UTF8String], -1, NULL);
    sqlite3_bind_text(stmt, 2, [ID UTF8String], -1, NULL);
    
    //4、执行sql语句
    result = sqlite3_step(stmt);
    if (result != SQLITE_DONE) {
        NSLog(@"修改失败");
        
        //关闭数据库和句柄
        sqlite3_close(sqlite);
        sqlite3_finalize(stmt);
        return NO;
    }
    
    //5、关闭数据库和句柄
    sqlite3_close(sqlite);
    sqlite3_finalize(stmt);
    
    return YES;
}

/**
 *  查询数据库
 */
+ (BOOL)quaryData
{
    //获取路径
    NSString *dbPath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingString:@"/user.sqlite"];
    
    //开启数据库
    sqlite3 *sqlite = nil;
    int result = sqlite3_open([dbPath UTF8String], &sqlite);
    if (result != SQLITE_OK) {
        NSLog(@"代开数据库失败");
        return NO;
    }
    
    //创建sql语句字符串
//    NSString *sqlStr = @"select * from user_info where user_age > ? and user_name = ?";
        NSString *sqlStr = @"select * from user_info where user_age > ?  and user_id like ?";
    
    //编译sql语句字符串
    sqlite3_stmt *stmt;
    result = sqlite3_prepare(sqlite , [sqlStr UTF8String], -1, &stmt, NULL);
    if (result != SQLITE_OK) {
        NSLog(@"SQL语句编译失败");
        //关闭数据库和句柄
        sqlite3_close(sqlite);
        sqlite3_finalize(stmt);
        return NO;
    }
    
    //绑定sql字符串上的数据
    NSInteger age = 100;
//    NSString *name = @"Tom";
        NSString *str = @"108%";
    sqlite3_bind_int64(stmt, 1, age);
//    sqlite3_bind_text(stmt, 2, [name UTF8String], -1, NULL);
        sqlite3_bind_text(stmt, 2, [str  UTF8String], -1, NULL);
    
    //执行语句
    result = sqlite3_step(stmt);
    while (result == SQLITE_ROW) {
        /**
         *  句柄、在数据库中的角标
         */
        char *name = (char *)sqlite3_column_text(stmt, 0);
        char *ID = (char *)sqlite3_column_text(stmt, 1);
        sqlite_int64 age = sqlite3_column_int64(stmt, 2);
        
        NSString *nameStr = [NSString stringWithCString:name encoding:NSUTF8StringEncoding];
         NSString *idStr = [NSString stringWithCString:ID encoding:NSUTF8StringEncoding];
        
        NSLog(@"user_name = %@,user_id = %@,uiser_age = %lld\n",nameStr,idStr,age);
        
        //执行下一条数据，如果不执行，就会在当前所查到的行数不断地循环执行
        result = sqlite3_step(stmt);
    }
    
    //5、关闭数据库和句柄
    sqlite3_close(sqlite);
    sqlite3_finalize(stmt);
    
    
    return YES;
}