I agree when you upgrade you should be adding columns or adding tables to your database. Most of the onupgrade samples actually suck because why am I deleting all this data then recreating the table? I found this blog entry I call it the Adams Incremental Update Method. It also handles situations where users may … Read more
Your query should go like this: INSERT INTO newDatabase.table1 (Column1, Column2) SELECT column1, column2 FROM oldDatabase.table1; UPDATE Since this answer is getting more attention than I even anticipated, I should expand on this answer. First of all, it might not be obvious from the answer itself, but the columns do not need to have the … Read more
You need to edit your my.cnf file and make sure you have the port set as in the following line: port = 3360 Then restart your MySQL service and you should be good to go. There is no query you can run to make this change because the port is not a dynamic variable (q.v. … Read more
Use: SELECT t1.id, t1.parent_id, t1.name, t2.name AS parent_name, t2.id AS parent_id FROM tbl t1 LEFT JOIN tbl t2 ON t2.id = t1.parent_id START WITH t1.id = 1 CONNECT BY PRIOR t1.id = t1.parent_id
This is not to be considered an exhaustive answer, but just a few points on the topic. Since the question is also tagged with the [sql] tag, let me say that, in general, relational databases aren’t particularly suitable for storing data using the EAV model. You can still design an EAV model in SQL, but … Read more
Call requery() on the Cursor when you change data in the database that you want reflected in that Cursor (or things the Cursor populates, like a ListView via a CursorAdapter). A Cursor is akin to an ODBC client-side cursor — it holds all of the data represented by the query result. Hence, just because you … Read more
Well why don’t you just ask? 🙂 Let me try to pin down my understanding of your requirement. It seems to me that you are looking at a thread being a linear list (not a tree) of messages between two people. I would think that you might want to allow more people in than just … Read more
Execute: python manage.py dumpdata > datadump.json Next, change your settings.py to the mysql database. Finally: python manage.py loaddata datadump.json
Ok, before you run into bigger problems you should know that SQLite is limited on the ALTER TABLE command, it allows add and rename only no remove/drop which is done with recreation of the table. You should always have the new table creation query at hand, and use that for upgrade and transfer any existing … Read more
After some googling, I found the advice to do the following, and it worked: SQL> startup mount ORACLE Instance started SQL> recover database Media recovery complete SQL> alter database open; Database altered