message: Correct IF EXISTS for alter table
diff: @@ -21,7 +21,7 @@ unique_ptr<AlterStatement> Transformer::TransformAlter(duckdb_libpgquery::PGNode
  // first we check the type of ALTER
  for (auto c = stmt->cmds->head; c != nullptr; c = c->next) {
  auto command = reinterpret_cast<duckdb_libpgquery::PGAlterTableCmd *>(lfirst(c));
  - AlterEntryData data(qname.catalog, qname.schema, qname.name, command->missing_ok);
  + AlterEntryData data(qname.catalog, qname.schema, qname.name, stmt->missing_ok);
  // TODO: Include more options for command->subtype
  switch (command->subtype) {
  case duckdb_libpgquery::PG_AT_AddColumn: {
  