Question

我的表中有5列，其中3个值来自一个保存方法，2个来自另一个。当我从第一个保存方法插入数据时，前3列被填充，现在我想要其他2列由下一个更新方法填充，但在同一行。我尝试使用ID进行更新，但这只是在特定行中更新。 P.S：我是iOS＆amp;的新手第一次使用sqlite。在这里我做了什么： -

-(BOOL)createDB
{
    NSString *docsDir;
    NSArray *dirPaths;
    // Get the documents directory
    dirPaths = NSSearchPathForDirectoriesInDomains
    (NSDocumentDirectory, NSUserDomainMask, YES);
    docsDir = dirPaths[0];
    // Build the path to the database file
    databasePath = [[NSString alloc] initWithString:
                    [docsDir stringByAppendingPathComponent: @"Calendardatabase.db"]];

    NSLog(@"%@",databasePath);
    BOOL isSuccess = YES;
    NSFileManager *filemgr = [NSFileManager defaultManager];
    if ([filemgr fileExistsAtPath: databasePath ] == NO)
    {
        const char *dbpath = [databasePath UTF8String];
        if (sqlite3_open(dbpath, &database) == SQLITE_OK)
        {
            char *errMsg;
            const char *sql_stmt =

"create table if not exists CalendarDataTable (ID INTEGER PRIMARY KEY AUTOINCREMENT,pl1 text, recordedTmpFile text,NavlabelDate text,eventTypeImgView text,eventNameLblP2 text)";
            if (sqlite3_exec(database, sql_stmt, NULL, NULL, &errMsg)
                != SQLITE_OK)
            {
                isSuccess = NO;
                NSLog(@"Failed to create table");
            }
            sqlite3_close(database);
            return  isSuccess;
        }
        else {
            isSuccess = NO;
            NSLog(@"Failed to open/create database");
        }
    }
    return isSuccess;
}


-(BOOL)saveData:(NSString*)pl1 recordedTmpFile:(NSString*)recordedTmpFile NavlabelDate:(NSString*)NavlabelDate eventTypeImgView:(NSString*)eventTypeImgView eventNameLblP2:(NSString*)eventNameLblP2;
//-(BOOL)saveData:(NSString*)eventTypeImgView eventNameLblP2:(NSString*)eventNameLblP2 pl1:(NSString*)pl1 pl2:(NSString*)pl2 pl3:(NSString*)pl3 pl4:(NSString*)pl4;
{
    const char *dbpath = [databasePath UTF8String];
    if (sqlite3_open(dbpath, &database) == SQLITE_OK)
    {
        NSString *insertSQL = [NSString stringWithFormat:@"insert into CalendarDataTable (pl1,recordedTmpFile,NavlabelDate,eventTypeImgView,eventNameLblP2) values (\"%@\",\"%@\",\"%@\",\"%@\",\"%@\")",pl1,recordedTmpFile,NavlabelDate,eventTypeImgView,eventNameLblP2];


        //   NSString *insertSQL = [NSString stringWithFormat:@"insert into CalendarDataTable (eventTypeImgView, eventNameLblP2 pl1 pl2 pl3 pl4) values (\"%@\",\"%@\",\"%@\",\"%@\",\"%@\",\"%@\")",eventTypeImgView,eventNameLblP2,pl1,pl2,pl3,pl4];


        const char *insert_stmt = [insertSQL UTF8String];
        sqlite3_prepare_v2(database, insert_stmt,-1, &statement, NULL);
        if (sqlite3_step(statement) == SQLITE_DONE)
        {
            return YES;
        }
        else
        {
            return NO;
        }
     //   sqlite3_reset(statement);
    }
    return NO;
}


-(BOOL)UpdateTable:(NSString*)eventTypeImgView eventNameLblP2:(NSString*)eventNameLblP2;
{
    const char *dbpath = [databasePath UTF8String];
    if (sqlite3_open(dbpath, &database) == SQLITE_OK)
    {
        NSString *updateSQL = [NSString stringWithFormat:@"UPDATE  CalendarDataTable set eventTypeImgView='%@',eventNameLblP2='%@' where ID=1",eventTypeImgView,eventNameLblP2];
        NSLog(@"%@",updateSQL);
        const char *insert_stmt = [updateSQL UTF8String];
        sqlite3_prepare_v2(database, insert_stmt,-1, &statement, NULL);
        if (sqlite3_step(statement) == SQLITE_DONE)
        {
            return YES;
        }
        else
        {
            return NO;
        }
      //  sqlite3_reset(statement);
    }
    return NO;
}

Answer 1

如果您要问UpdateTable... saveData...方法中保存的行，您可以使用自定义标识符，该标识符以某种方式从saveData...中插入的数据生成。

假设为名为CalendarDataTable的{{1}}添加一个额外字段，并在其中存储一些唯一生成的值，例如当前时间戳created，存储时间戳并使用它们{{1} } [NSDate timeIntervalSinceReferenceDate] * 1000

的子句

使用ID，sqlite更新同一行中的列

1 个答案: