How to Manipulate X-axis of chart

Question

I have made a chart and added the points on runtime. The data is plotted as Chart1.ChartAreas(0).AxisX.IntervalType = DateTimeIntervalType.Weeks Chart1.Series("PH").Points.AddXY(DateTime.Parse(dr.Item("readtime")).ToString("MM-dd"), dr.Item("ph")) The data that is plotted holds 7 days of data. As shown below, the date is repeated.

How to achieve the x axis showing only 11-08, 11-13, 11-14 in this case?

Here is a sample data

Answer 1

When you get data from database, use like this,

SELECT SUM(ph),SUM(tmp),SUM(orp),SUM(sal),SUM(ec),SUM(tds),SUM(do),readtime
FROM <your tables>
GROUP BY readtime

The results set returned from this query is the thing you are looking for....

Answer 2

The data that you show is obviously invalid data.

You have several zero readings occurring at exactly the same time - midnight.

I suspect these are not even real readings.

You need to exclude them (and you should probably find out why this is happening - maybe a parsing error?)