PgConf.Russia 2016

Common Java wisdom is to use PreparedStatements and Batch DML in order to achieve top performance. It turns out one cannot just blindly follow the best practices. In order to get high throughput, you need to understand the specifics of the database in question, and the content of the data.

In the talk we will see how proper usage of PostgreSQL protocol enables high performance operation while fetching and storing the data. We will see how trivial application and/or JDBC driver code changes can result in dramatic performance improvements. We will examine how server-side prepared statements should be activated, and discuss pitfalls of using server-prepared statements.

Unlike most other databases, PostgreSQL is developed by a community, and not by a company or even a foundation. Those who have been members of this community for a long time generally consider this a strength, but it can often be confusing to outsiders who are more used to dealing with traditional organization. For those who are not already on the inside, this talk will give an introduction to how the PostgreSQL community works and how the different parties interact, as well as how this has evolved over the years.

Enterprises need enterprise-level databases. The existing Postgres clustering solutions are not supported by the community. Postgres needs a community-supported cluster solution. There have been multiple attempts like Postgres-XC/XL, but they are still being developed separately and have low chance to be accepted by the community. Other solutions, like pg_shard, plproxy, FDW-based, etc. lack the notion of global transactions. We developed a Distributed Transaction Manager (DTM) as a Postgres extension to achieve global consistency over a number of Postgres instances. To demonstrate the capabilities of the DTM we present examples of distributed transaction processing using pg_shard and postgres_fdw. We hope that the proposed approach will be included into Postgres 9.6. This will make the development of the clustering solutions easier for all interested parties.

This talk will cover "hasql", a highly-efficient library for integration of Haskell and PostgreSQL. The library provides an API for declarative programming, which is also quite flexible and terse. The talk will cover the benefits of declarative programming as well as the architectural and technical solutions behind the library, including the implementation of the PostgreSQL binary protocol. Hasql is used in PostgREST, a popular modern restful API for Postgres.