Upgrade From Mendix 3.3.7 to 4

Hi We are upgrading from Mendix 3 to 4.5.2 (and very excited about it) :) I noticed that the upgrade entails updating all the ID fields with new values. Why would this be? DROP INDEX "IDXSOMEINDEX"; ALTER TABLE "SOME$TABLE" DROP CONSTRAINT "PK1642604545" DROP INDEX; ALTER TABLE "SOME$TABLE" MODIFY ("ID" number(20)); UPDATE "SOME$TABLE" SET "ID" = "ID" + 77687093572141056 - BITAND("ID", 77687093572141056); ALTER TABLE "SOME$TABLE" ADD CONSTRAINT "PK1642604545" PRIMARY KEY("ID"); CREATE INDEX "IDXSOMEINDEX" ON "SOME$TABLE" ("SOMECOLUMN","ID"); We have reporting and down-stream systems running off our application, and this would have a massive impact on these systems. Also, executing the entire script would not finish in a single day, as the database is huge, with hundreds of tables and millions upon millions of records. We would need to work on a alternative upgrade solution, so we need to know why this is done on the upgrade. Kind Regards Frikkie
1 answers

This is actually required for your update from 3 to 4, the ids are not simply changed but their size is increased to 64 bits to be able to deal with tables with many records.

You can see the details at https://world.mendix.com/display/refguide4/Moving+from+3+to+4