Transactional DDL workflow for MySQL

Question

I was a little surprised to discover that DDL statements (alter table, create index etc) implicitly commit the current transaction in MySQL. Coming fr

Answer 1

One possibility is doing DDL changes in a non-destructive-manner, which would include:

• split logic in DDL/DCL (+1 to reverse all) and DML
• run only the DDL/DCL script adding columns, new tables, ..
• depending on result:
  • on success, apply the DML changes,
  • on fail, apply reverse DDL/DCL script removing the stuff you wanted to add in second step (obviously with some errors "does not exist" depending on how far step 1 got)
• remove what is not needed anymore, drop old columns/tables