How to display blob images in Cognos Reports

Overview

One common requirement for reports is to display images store inside the database. When adding these tables and columns from database to Cognos Framework Manager Model, the image column are represent as ‘BLOBs’ inside the model and package.

When BLOB fields are use in Cognos Report Studio from the published package, none data is displayed.

Cognos does not support reporting ‘BLOB’ data types!

The Idea

The idea to work around this issue is to add a asp page that will get record information from the Cognos report, retrieve the image file from the database and return to Cognos as html displaying the actual image to be use a URL information in a image object in Cognos Report Studio.

Considerations / Impacts / Challenges

       Security: Security will have some limitation with this approach, however, security could be apply in many different ways according to each environment and requirements.

Observations

Diagram:

ASP Page Code (sample)

<% @language=VBScript %>
<%
Dim ONES
Set ONES = Server.CreateObject("ADODB.Connection")
ONES.ConnectionTimeout = 15
ONES.CommandTimeout = 30

ONES.Open "Provider=SQLNCLI; Server=WINS-DATABASE\WINS2012; Database=name; Uid=user; Pwd=password;"

Dim rs

Set rs= ONES.execute("select imagecolumn from imagetable where id='" & Request.QueryString( "attach_id" ) & "'" )

If rs.eof=false then
Response.ContentType = rs(1)
<!--Response.Flush -->
Response.Buffer = True
Response.BinaryWrite rs(0)
Response.End
End If
rs.close
ONES.close
Set ONES=nothing
%>

ASP Page Location

Any location in the network that can be reach by the Cognos Report

Image Object in Report Studio: Change the URL property for the object to point to the asp page location

Hope this really helps. Please don’t forget to leave your comments and questions below. And keep Thinking Cognos :)