Concatenate a string onto column headers

[dxwallace]

I thought this was a simple issue but it's not, can someoen please help!!

I am trying to add a string into the column headers for multiple items of a report. Since string will be for many columns, and I am trying to create a field instead of just hardcoding the string (which is 'SPD") to to the end of the column header. The column header is a [Query1].[Month].  I want to create another data item called [Query1].[ColHeader] which I set to the value of ' SPD' in the expression editor. However when I to use a column header defined as [Query1].[Month] + [Query1].[ColHeader] I get an error saying that the second part is an invalid expression.

Can someone tell me why?

[ajax6262]

Create your data item, but make sure that the expression is ' SPD' (including the space).  Then unlock the column header cells, and drag the spd data item into the header cell next to the default header.

[dxwallace]

How do you unlock the column header cells?

[dxwallace]

Nevermind that last question, I saw that there was a lock icon on the toolbar and that did the trick.

Thanks

[dxwallace]

However, when I unlock the report and drag the String field in, there is nothing showing on the report. Can you tell me why that is?

[dxwallace]

I changed the "Source Type" attribute in the properties pane to "report expression" from "data item value" (since that was the same attribute that I am trying to concatenate to) and now I can see the " SPD" in the column header.

If someone can tell me why I did what I did works, that would be cool