Tech

Methods of SQLite to PostgreSQL Migration

In the modern era, DBMS is the backbone of most business applications that’s why it is extremely important to make the best decision when choosing it and to be ready for upgrade if the current database management system does not fit business needs anymore. While SQLite is a popular choice for individual applications due to its simplicity and cost-effectiveness, it falls short when it comes to sharing data across multiple applications or users as well as handling huge volumes of data. To resolve this issue, companies and organizations have to migrate from SQLite to more robust DBMS, such as PostgreSQL. In this article, we will discuss the tips for migrating an SQLite database to PostgreSQL.

Manual Migration from SQLite to PostgreSQL

One of the most straightforward techniques of migrating databases from SQLite to PostgreSQL is to export the source database into an intermediate CSV format and then import it into PostgreSQL. This involves using the following commands to export data from SQLite databases into CSV format:

sqlite> .headers on

sqlite> .mode csv

sqlite> .output data.csv

sqlite> SELECT * FROM customers;

sqlite> .quit

The resulting CSV file can then be imported into PostgreSQL using the pgloader tool, which automates the process of data migration. However, there are some nuances requiring special attention, such as converting specific types like BLOB into BYTEA and datetime into timestamp, and handling different means of escaping strings.

Commercial Toolsfor SQLite to PostgreSQL Migration

A more efficient approach to SQLite to PostgreSQL database migration would be to use commercial software that can automate the overall conversion process with a few clicks of the mouse. One such advanced tool that provides the required functionality for high efficient database migration is the SQLite to PostgreSQL converter. This product supports all modern versions of PostgreSQL servers running on Linux/Unix and Windows, as well as DBaaS variations (Heroku, Azure, Amazon RDS) and allows the modification of the resulting table structure during migration.

SQLite to PostgreSQL converter has easy to use wizard-style GUI that guides users through all database migration steps:

  • Select how to migrate SQLite database – move to PostgreSQL directly or export into PostgreSQL script file containing SQL-statements to build all database entries and insert the data

  • If ‘Migrate to PostgreSQL server directly’ option has been chosen on the previous step, now it is necessary to specify connection settings for the destination PostgreSQL server

  • Next step is to select SQLite database file and the target PostgreSQL database. If you specify existing PostgreSQL database in direct migration scenario, the tool ask how to process it: overwrite all, overwrite exiting tables only, merge or synchronize.

  • Next step is to customize the database migration. Specify the target schema, how to create PostgreSQL tables and insert the data.

  • On the next step user has select SQLite tables to migrate into PostgreSQL database:

Click ‘Next’ button and database migration process will be launched with progress indication on the next wizard screen.

Post-migration Steps

Regardless of the method chosen, it is crucial to verify that the migration result is correct before releasing the target database in production. Here is a checklist of steps to be done during the migration process:

  • Firstly, plan the migration carefully. This phase includes selecting the most appropriate tools and frameworks to automate the migration procedure and determining the order in which to migrate the data.
  • Secondly, test the migration on a small dataset. This step helps to diagnose and fix any problems that may arise before migrating the entire database.
  • Thirdly, make a backup of the original database before starting the migration. This is probably the most important step that helps to ensure the original data is not lost in case of any issues or unexpected behavior of migration tools.
  • Fourthly, monitor the migration process closely. This step is dedicated to monitoring the performance of the database and ensuring that the data is accurate after the conversion is completed.
  • Lastly, document the migration process. On this step, all migration actions must be recorded, as well as any issues encountered and how they were resolved.

In conclusion, migrating an SQLite database to PostgreSQL requires careful planning, testing, and monitoring. While exporting data to CSV format and using the pgloader tool can be an effective approach, commercial software like SQLite to PostgreSQL converter can make the process more efficient. Regardless of the method chosen, it is essential to verify the migration result and document the migration process. Interested parties can visit the official site of the vendor company to learn more about the SQLite to PostgreSQL converter.