How to convert a postgres database to sqlite

Question

We\'re working on a website, and when we develop locally (one of us from Windows), we use sqlite3, but on the server (linux) we use postgres. We\'d like to be able to impor

Answer 1

Taken from https://stackoverflow.com/a/31521432/1680728 (upvote there): The sequel gem makes this a very relaxing procedure:

First install Ruby, then install the gem by running gem install sequel.

In case of sqlite, it would be like this: sequel -C postgres://user@localhost/db sqlite://db/production.sqlite3

Credits to @lulalala .

Answer 2

In case one needs a more automatized solution, here's a head start:

#!/bin/bash

$table_name=TABLENAMEHERE

PGPASSWORD="PASSWORD" /usr/bin/pg_dump --file "results_dump.sql" --host "yourhost.com" --username "username" --no-password --verbose --format=p --create --clean --disable-dollar-quoting --inserts --column-inserts --table "public.${table_name}" "memseq"

# Some clean ups
perl -0777 -i.original -pe "s/.+?(INSERT)/\1/is" results_dump.sql
perl -0777 -i.original -pe "s/--.+//is" results_dump.sql

# Remove public. prefix from table name
sed -i "s/public.${table_name}/${table_name}/g" results_dump.sql

# fix binary blobs
sed -i "s/'\\\\x/x'/g" results_dump.sql

# use transactions to make it faster
echo 'BEGIN;' | cat - results_dump.sql > temp && mv temp results_dump.sql
echo 'END;' >> results_dump.sql

# clean the current table 
sqlite3 results.sqlite "DELETE FROM ${table_name};"

# finally apply changes
sqlite3 results.sqlite3 < results_dump.sql && \
rm results_dump.sql && \
rm results_dump.sql.original

Answer 3

It was VERY easy for me to do using the taps gem as described here: http://railscasts.com/episodes/342-migrating-to-postgresql

And I've started using the Postgres.app on my Mac (no install needed, drop the app in your Applications directory, although might have to add one line to your PATH envirnment variable as described in the documentation), with Induction.app as a GUI tool to view/query the database.

Answer 4

I found this blog entry which guides you to do these steps:

1. Create a dump of the PostgreSQL database.

   ssh -C username@hostname.com pg_dump --data-only --inserts YOUR_DB_NAME > dump.sql
   

2. Remove/modify the dump.

   1. Remove the lines starting with SET
   2. Remove the lines starting with SELECT pg_catalog.setval
   3. Replace true for ‘t’
   4. Replace false for ‘f’

3. Add BEGIN; as first line and END; as last line

4. Recreate an empty development database. bundle exec rake db:migrate

5. Import the dump.

   sqlite3 db/development.sqlite3
   sqlite> delete from schema_migrations;
   sqlite> .read dump.sql
   

Of course connecting via ssh and creating a new db using rake are optional

Answer 5

There are some converter tools around:

https://www2.sqlite.org/cvstrac/wiki?p=ConverterTools

Would it be easier just to install postgres on windows?

Probably, and doing so is very straightforward.

Answer 6

STEP1: make a dump of your database structure and data

pg_dump --create --inserts -f myPgDump.sql -d myDatabaseName -U myUserName -W myPassword

STEP2: delete everything except CREATE TABLES and INSERT statements out of myPgDump.sql (using text editor)

STEP3: initialize your SQLite database passing structure and data of your Postgres dump

sqlite3 myNewSQLiteDB.db -init -myPgDump.sql

STEP4: use your database ;)