Power Query - Newbie Question - Comparing Two Columns with Dates

[kittensandclimb]

Hello:

Power Query newbie here. 

I have a Query in Power Query.

There is a Column called "Start Date" and there is a column called "T-2" Date.

I would like to compare these two columns. If these two columns match in date, I would like to return a new column that states "Yes."

I am having trouble writing this. Something as simple as the below is giving me an error.

if [Start Date] = [T-2 Date] then yes else no

[Omid_Motamedise · Accepted solution]

if you want to copare row by row, go to add column tab pick custom column tab in the oppened window use the next formula

if [Start Date] = [T-2 Date] then "yes" else "no"

but if you want to check the whole table once, use the next formula in a  new step. (imagin your previous step name is Source)

Source[Start Date] = Source[T-2 Date]

[ronrsnfld]

You need to put strings within quotes, unless you have defined yes and no as variables. 

Also, you "T-2" Date column name looks strange with quotes around the first word and none around the second. So if that is not an error, your syntax is off.