I have a variable named #cfData# which contains an array of structures. As it's clear from the image, for 1st structure array there are 6 keys and for 2nd, only two keys,viz date and open.

If I run a common loop, to go through each and every key, I will get an error at second array element. So the following only works when all the keys are present in the structure:
<cfset blockedtotal = 0 />
<cfset bouncetotal = 0 />
<cfset blocked = 0/>
<cfset datetotal = 0 />
<cfloop array = #cfData# index = "i">
<cfset blockedtotal += i.blocked />
<cfset bouncetotal += i.bounce />
</cfloop>
After reading online, I got an idea of using StructKeyExists where I think I can proceed in the following way:
<cfif structKeyExists(cfData,"bounce")>
<cfoutput>Bounce:#cfData.bounce#"/></cfoutput>
<cfelse>
<cfoutput> Bounce : [none]<br/></cfoutput>
</cfif>
But I am wondering, where exactly should I insert the above code inside the cfloop? Please advise if my approach is wrong.
Update:
Thanks guys. I got it running by using the following code based on the answers and it's running fine:
<cfloop array="#cfData#" index="i">
<cfif structKeyExists(i, "date")>
<cfset counter++>
<cfoutput>#counter#</cfoutput> Date is: <cfoutput> #i.date#</cfoutput> <br/>
</cfif>
</cfloop>