VBA ADODB : replace the missing date (timestamp format)

Hello Experts,

My question is simple, but can’t find the answer 😞

I would like to replace the missing value in column  d_fin by the value 31/12/2999 00:00:00 but it seems that coalesce function doesn’t work on VBA. I’m trying select case when but I have the error. Do you know how to replace the missing value in ADODB VBA ? Thank you !