Exclusion Script Content Block - Prevent duplicates

SFMC-AMPscript-exclusion-script-content-block.amp

%%[

var @contextInsertDate

set @contextInsertDate = AttributeValue("YOUR_TSD_DE_INSERT_DATE")
set @contextInsertDate = format(@contextInsertDate,"yyyyMMddhhmmss")

var @exclude
set @exclude = 0

var @rows
var @rowCount

set @rows = LookupOrderedRows("YOUR_TSD_DE", 1, "YOUR_TSD_DE_INSERT_DATE", "YOUR_KEY_VALUE_FOR_SUBSCRIBER_SEND", AttributeValue("YOUR_KEY_VALUE_FOR_SUBSCRIBER_SEND"))
set @rowCount = rowcount(@rows)

if @rowCount > 0 then

  set @row = row(@rows, 1)

  set @oldestInsertDate = field(@row, "YOUR_TSD_DE_INSERT_DATE")
  set @oldestInsertDate = format(@oldestInsertDate, "yyyyMMddhhmmss")

  
  if @oldestInsertDate != @contextInsertDate then
    set @exclude = 1
  endif
  
  output(concat(@exclude))

endif

]%%