PGConf.Russia 2018

The report reviews approaches and implementattion options for the migration of Parus-Budget 8 client-server application from the Oracle Database platform to the PostgreSQL platform without changing the client application for Desktop and the Web. The proposed solution allows to make transparent transition of the existing users' workplaces.

How to optimize query processing in PostgreSQL? What if we deal with hundreds of servers and thousands of instances? The company "Tensor" has developed a special tool - explain.sbis.ru, which enables synchronous collection and analysis of queries, visualization of implementation plans, and monitoring of bugs in database.

"And telling GIN from SP-GIST was quite beyond his wit, we found", said the classic. Can you? This masterclass is about not-so-often used index types (compared to conventional B-tree) which however can do a great job for you. We will look into internal mechanics of these indexes and discuss cases where they can be successfully applied. Also we will talk about some peculiarities of PostgreSQL index access. To spend time efficiently, listeners are required to have basic knowledge of PostgreSQL and should be used to read plans of simple queries.

Materials of the master class

• Slides
• Demo 1
• Demo 2
• Demo 3

Backup copy of the database with demo data can be downloaded here:

• Recovery with pg_restore (338 MB)

Bringing the provability and immutability of blockchain to performance and efficiency of traditional DBMS.

Blockchain technology has several unique properties including provability and immutability. Every blockchain transaction is signed by its author, and it could be verified by any blockchain network member. Also, once data is stored in blockchain, it can't be altered in the future. Many databases operating traditional DBMS would also benefit from provability and immutability properties. However, inclusion of all the transaction data in the public blockchain is very expensive.

Credereum is the platform, which allows creation and maintaining of databases, whose contents and history are provable and immutable without sacrifice the performance and efficiency of traditional DBMS. Thanks to Credereum, database owner can prove the validity of query results, while users can verify them. Database owner don't have to reveal the whole database contents or full history of transactions to provide the proof of database query results. Therefore, Credereum database may contain private sensitive information. Credereum utilized bleeding-edge technologies including, but not limited to decentralized cloud, public blockchain with sharding. Credereum is an emerging technology of trusted and private databases.

We will explain why PostgreSQL is suitable database for Credereum and what we need to develop in Postgres to support signed transactions and cryptographic storage.