{"error":"Unknown exception","errorMessage":"Unexpected character ('_' (code 95)): was expecting comma to separate Object entries\n at [Source: (org.eclipse.jetty.server.HttpInputOverHTTP); line: 1, column: 132]","errorClass":"com.fasterxml.jackson.core.JsonParseException","host":null}
Passing the druid REPLACE Query as a string Object and got the error.
QQ when you run the same SQL command in the Druid Console, does the SQL work OK?
If it works in the console, that at least pins this down to the way that you're forming the SQL to POST.
If it doesn't work in the console, at least you know there there is a syntax issue with the REPLACE.