SQLite 的 REPLACE 功能在目标 c ios 上不起作用

Question

我正在使用 SQLite，但是当我替换它一次又一次添加到我的数据库中的数据时，基本上我想存储 alarm name、alarm type 和 alarm tune path，应该只有 6 rows 在NotiType 因为我在每一列中都插入了 6 个元素。但是这里的问题是当我每天更换警报名称类型和调整时的数据时，但是数据被插入到下面的每一列中，并且当表格调用替换数据函数时计数。

if([fileManager fileExistsAtPath:_dbPath] == YES) {
    const char *dbPathagain = [_dbPath UTF8String];
    if(sqlite3_open(dbPathagain, &_DB) == SQLITE_OK ) {
        NSLog(@"database is open");
        char *errorMessage;

        const char *sql_statement = "CREATE TABLE IF NOT EXISTS NotiType(Alarm TEXT, Type TEXT, TPath TEXT)";


        NSLog(@"created table success");
        // sqlite3_stmt *statement = NULL;
        //  const char *dbPathagain = [ _dbPath UTF8String];

        if([fileManager fileExistsAtPath:_dbPath] == YES) {
            sqlite3_stmt *statement = NULL;
            const char *dbPathagain = [_dbPath UTF8String];
            if(sqlite3_open(dbPathagain, &_DB) == SQLITE_OK ) {
                for(int itemIndex = 0; itemIndex < [azanst count];itemIndex++){

                    NSString *myname = [azanst objectAtIndex:itemIndex];
                    NSString *mytype = [alarmsstype objectAtIndex:itemIndex];
                    NSString *mytunepath = [alarmtune objectAtIndex:itemIndex];

                    NSString *insertSQLData = [NSString stringWithFormat:@"REPLACE INTO NotiType(Alarm, Type, TPath) VALUES (\"%@\", \"%@\",\"%@\")", myname, mytype, mytunepath];
                    NSLog(@"here is alarm names %@", myname);
                    NSLog(@"here alarm types %@", mytype);
                    NSLog(@"here alarm tune path %@", mytunepath);
                    const char *insert_statement = [insertSQLData UTF8String];

                    sqlite3_prepare_v2(_DB, insert_statement, -1, &statement, NULL);

                    if (sqlite3_step(statement) == SQLITE_DONE) {
                        NSLog(@"data added successfully");
                    }
                    else {
                        NSLog(@"could not add timings");
                    }
                }
                sqlite3_finalize(statement);
                sqlite3_close(_DB);
            }
        }
        if (sqlite3_exec(_DB, sql_statement, NULL, NULL, &errorMessage) != SQLITE_OK) {
            NSLog(@"failed to insert in table");
        }
        sqlite3_close(_DB);
    }
    else {
        NSLog(@"failed to open db or cretate table");
        NSLog(@"Database Error Message : %s", sqlite3_errmsg(_DB));
    }
}

更新

我正在做这样的事情

     for (i=0, i<= ID.count, i++) {

                    NSString *insertSQLData = [NSString stringWithFormat:@"UPDATE NotiType SET Alarm =" + myname "," + "Type =" + mytype "," + "Tpath =" mytunepath + " where ID == i"];
                    }

Answer 1

您忘记提供 WHERE 语句：

NSString *insertSQLData = [NSString stringWithFormat:@"REPLACE INTO NotiType(Alarm, Type, TPath) VALUES (\"%@\", \"%@\",\"%@\")", myname, mytype, mytunepath];

您应该添加类似 WHERE _id = %@, myAlarmUniqIdentifier 的内容，以确保您只更改正在编辑的那个

编辑：想想看，我也建议使用 UPDATE，我不确定 REPLACE 是否是你想要的......

UPDATE {table} SET {column1} = {editedObject.value1}, {column2} = {editedObject.value2} WHERE {uniqueIdField} = {editedObject.identifier};

编辑 2： 在您进行编辑后，像这样更新您的 for 循环：

 NSString *myname = [azanst objectAtIndex:i];
 NSString *mytype = [alarmsstype objectAtIndex:i];
 NSString *mytunepath = [alarmtune objectAtIndex:i];
 NSNumber *myid = [ID objectAtIndex:i]; //<-- get the unique identifier for the item number ‘i‘
[NSString stringWithFormat:@"UPDATE NotiType SET Alarm=%@, Type=%@, Tpath=%@ where ID=%@", myname, mytype, mytunepath, myid];