ios - 比较sqlite表中的整数？

Question

我的游戏中有一个高分表。游戏结束后，屏幕上会显示分数并将其插入高分表。我想知道如何将新分数与表中的最高分数进行比较，以便让用户知道他们是否获得了高分。下面我包含了我用来更新分数并将其插入表中的代码。保留的分数是一个整数，globalScore。

-(void)updateScores:(NSInteger)Primary_key
{
    sqlite3_stmt *statement=nil;
    NSString  *sql=nil; 
    @try
    {
        statement=nil;
        sql=nil;    


        sql=[NSString stringWithFormat:@"update tblHard set Score=? where id=%d",Primary_key];


        if(sqlite3_prepare_v2(database, [sql UTF8String], -1, &statement, NULL)!=SQLITE_OK)
        {
            NSAssert1(0, @"Error: failed to prepare statement with message '%s'.", sqlite3_errmsg(database));
        }

        sqlite3_bind_int(statement, 1, globalScore);

        int success=sqlite3_step(statement);

        if (success == SQLITE_ERROR) {

            NSAssert1(0, @"Error: failed to insert into the database with message '%s'.", sqlite3_errmsg(database));
        }
        sqlite3_finalize(statement);
        statement=nil;
        sql=nil;
    }
    @catch (NSException *e) 
    {
        NSLog(@"asd");
    }
}

-(int)InsertGame
{
    int i=0;
    sqlite3_stmt *statement=nil;
    NSString  *sql=nil; 
    @try
    {
        statement=nil;
        sql=nil;    


        sql=[NSString stringWithFormat:@"insert into tblHard(Score) values (?)"];


        if(sqlite3_prepare_v2(database, [sql UTF8String], -1, &statement, NULL)!=SQLITE_OK)
        {
            NSAssert1(0, @"Error: failed to prepare statement with message '%s'.", sqlite3_errmsg(database));
        }

        sqlite3_bind_int(statement, 1, globalScore);

        int success=sqlite3_step(statement);

        if (success == SQLITE_ERROR) {

            NSAssert1(0, @"Error: failed to insert into the database with message '%s'.", sqlite3_errmsg(database));
        }
        i= sqlite3_last_insert_rowid(database);
        sqlite3_finalize(statement);
        statement=nil;
        sql=nil;
    }
    @catch (NSException *e) 
    {
        NSLog(@"asd");
    }
    return i;
}

所以我正在寻找的是这样的东西......

if(globalScore > "the highest score in the table"){
highscorelabel.hidden=NO;
}

Answer 1

您可以检索表中的最高分

select max(Score) from tblHard

您可以使用 sqlite3_column_int 检索此 SQL 查询的结果。这是代码(为简洁起见删除了错误检查):

int highestScore;
/* ... */
sqlite3_prepare_v2(database, "select max(Score) from tblHard", -1,
                   &statement, NULL);
sqlite3_step(statement);
highestScore = sqlite3_column_int(statement, 0);

然后你可以将当前的最高分数与globalScore进行比较:

if (globalScore > highestScore) {
    /* ... */
}