At the moment, I am comparing the fields from the dump file and the fields in our models.py. There are fields that exist on the dump file that are not yet in our existing model/models that why I want to know if should I modify the schema of our database to match the dump file of the client. I'm lost on this, sorry.
On Thu, Apr 12, 2018 at 8:46 AM, Mike Dewhirst <mi...@dewhirst.com.au> wrote: > On 12/04/2018 9:47 AM, tango ward wrote: > >> Hi Mike, >> >> >> Thanks for the advice. >> >> May I ask as well, on Django side, since we have already an existing >> system, how should I adjust the fields that are existing from the dump file >> to the Django? Should I just add fields in models.py? >> > > Treat that as a separate task. You can do it before the migration or > after. I would preferdo it afterwards because I am more comfortable with > Postgres. And I suspect Postgres will be a better fit with Django. > > However, I'm not sure what you mean exactly by adjusting fields. Your last > question above indicates you want to change the schema in an existing > Django project. You need to consider when the fields need to be changed in > the context of real-world pressures from your production system users. It > might need to be sooner rather than later and that may force adjustments > prior to the move to Postgres. > > If there are problems with the existing MySQL system it would be best to > fix them before switching. > > The bottom line is that preparations and testing for the move has to > happen in parallel with ongoing support and maintenance and possibly > ongoing development of the production system. When you are ready to switch > and happy that it will go like clockwork the actual switch can be scheduled > as a definable task in the ongoing workflow. All developers will have to > switch at the same time - or prior if they can have access to your > completed scripts for their personal development databases. > > hth > > Mike > > >> On Thu, Apr 12, 2018 at 6:42 AM, Mike Dewhirst <mi...@dewhirst.com.au >> <mailto:mi...@dewhirst.com.au>> wrote: >> >> On 11/04/2018 11:40 PM, tango ward wrote: >> >> Hi there, >> >> This will be my first time to migrate a database in my first >> programming job. I checked the dump file today and load it in >> MySQL benchmark to view the ERD. The database that I need to >> migrate has 48 tables and has existing data already. >> >> >> I would like to know what are the things that I need to do >> first. I'm gonna test the migration first in my local machine >> before bringing it to live production. I am currently reading >> https://wiki.postgresql.org/wiki/Converting_from_other_Datab >> ases_to_PostgreSQL >> <https://wiki.postgresql.org/wiki/Converting_from_other_Data >> bases_to_PostgreSQL>. >> >> >> >> >> Any suggestions will be highly appreciated. >> >> >> 1. Do the migration locally >> >> 2. Devise some repeatable automated success tests to prove the >> migration works >> >> 3. Set up a new VM as an exact duplicate production machine >> running MySQL. Use your hosts file to put its IP address somewhere >> else than the DNS points to. Beware that ACLs often use IP >> addresses rather than host names. >> >> 4. Do the migrations and run the tests on the duplicate machine. >> Debug as necessary. >> >> 5. Announce to users that the system is going down for planned >> maintenance >> >> 6. Remove your hosts file adjustment so your system is back to >> looking at the real production machine >> >> 7. Take production off-line and do a pre-migration dump or backup >> from which you can restore if things go wrong >> >> 8. Do the migration, run the tests then restore service >> >> I have done such things in the distant past but not recently. I >> may have forgotten something but in my opinion items 5 and 7 above >> are super critical. >> >> Good luck >> >> Mike >> >> >> >> Thanks, >> J >> -- You received this message because you are subscribed >> to the >> Google Groups "Django users" group. >> To unsubscribe from this group and stop receiving emails from >> it, send an email to django-users+unsubscr...@googlegroups.com >> <mailto:django-users%2bunsubscr...@googlegroups.com> >> <mailto:django-users+unsubscr...@googlegroups.com >> <mailto:django-users%2bunsubscr...@googlegroups.com>>. >> To post to this group, send email to >> django-users@googlegroups.com >> <mailto:django-users@googlegroups.com> >> <mailto:django-users@googlegroups.com >> <mailto:django-users@googlegroups.com>>. >> Visit this group at >> https://groups.google.com/group/django-users >> <https://groups.google.com/group/django-users>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/django-users/CAA6wQLKcf22a >> XXKd6xUn%3DT6HOxHLBN7u1xcn%3DOXO3DdL%3D54XSg%40mail.gmail.com >> <https://groups.google.com/d/msgid/django-users/CAA6wQLKcf22 >> aXXKd6xUn%3DT6HOxHLBN7u1xcn%3DOXO3DdL%3D54XSg%40mail.gmail.com> >> <https://groups.google.com/d/msgid/django-users/CAA6wQLKcf22 >> aXXKd6xUn%3DT6HOxHLBN7u1xcn%3DOXO3DdL%3D54XSg%40mail. >> gmail.com?utm_medium=email&utm_source=footer >> <https://groups.google.com/d/msgid/django-users/CAA6wQLKcf22 >> aXXKd6xUn%3DT6HOxHLBN7u1xcn%3DOXO3DdL%3D54XSg%40mail. >> gmail.com?utm_medium=email&utm_source=footer>>. >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. >> >> >> >> > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-users+unsubscr...@googlegroups.com. > To post to this group, send email to django-users@googlegroups.com. > Visit this group at https://groups.google.com/group/django-users. > To view this discussion on the web visit https://groups.google.com/d/ms > gid/django-users/07a26b64-9923-f9ee-b6c2-47676d245038%40dewhirst.com.au. > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Django users" group. 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