Load sqlite database into Postgres

Question

I have been developing locally for some time and am now pushing everything to production. Of course I was also adding data to the development server without thinking that I hadn't reconfigured it to be Postgres.

Now I have a SQLite DB who's information I need to be on a remote VPS on a Postgres DB there.

I have tried dumping to a .sql file but am getting a lot of syntax complaints from Postgres. What's the best way to do this?

Answer 1

For pretty much any conversion between two databases the options are:

1. Do a schema-only dump from the source database. Hand-convert it and load it into the target database. Then do a data only dump from the source DB in the most compatible form of SQL dump it offers. Try loading that into the target DB. When you hit problems, script transformations to the dump using sed/awk/perl/whatever and try again. Repeat until it loads and the results match.

2. Like (1), hand-convert the schema. Then write a script in your preferred language that connects to both databases, SELECTs from one, and INSERTs into the other, possibly with some transformations of data types and representations.

3. Use an ETL tool like Talend or Pentaho to connect to both databases and convert between them. ETL tools are like a "somebody else already wrote it" version of (2), but they can take some learning.

4. Hope that you can find a pre-written conversion too. Heroku one called sequel that will work for SQLite -> PostgreSQL; is it available without Heroku and able to function without all the other Heroku infrastructure and code?

After any of those, some post-transfer steps like using setval() to initialize sequences is typically required.