PgConf.Russia 2020

I will share our experience of migrating a server application for Russian railways from Oracle 11g Standard Edition to vanilla PostgreSQL 11.5.
At the time of migration, the database contained about 200 stored procedures of over 60000 lines of Oracle PL/SQL code (which has been developed since 2006, that is, for more than 12 years), about 250 tables, and 50GB of data.
Starting with a prologue, we'll describe our adventures along the migration process, as well as pleasant and unpleasant surprises we encountered, and finally get to an epilogue and a happy end. The story is told on behalf of an Oracle user exploring Postgres.

Will be demonstrated in the master-class the following: 1). The benefits of declarative programming. Rapid creation of complex LUI-forms using only SQL. 2). Support for long transactions and automatic locks. An example of a wizard with a record directly in the database. 3). The multilingual fields and columns. Rapid inclusion of multilingualism in existing forms. 4). Control the coloring of data in fields and columns of the form. Typical examples. 5). Live search in input fields using the example of address input. 6). How to configure the LUI to enter and display of application-specific data. 7). Design form Master Detail with retrieving data from two different databases. 8). How end-user builds of complex data queries without using SQL.

Odyssey is a new PostgreSQL connection pooler designed for the high-load environment. It can significantly scale processing performance by specifying the number of additional worker threads. This allows to increase SSL/TLS performance and provide more balanced pooling control using by sharing global server connection pools. In this talk I will answer 4 questions: 1. When you should use connection pooler? When Odyssey is the most optimal choice? 2. How to set up a cluster with Odyssey? 3. How to sleep well and be sure that everything works? 4. How does the architecture of Odyssey look like? How to implement or propose feature that you want?

At the master class, we will learn how to execute fast load tests of Postgres databases: optimizing database configurations, data structure, indexes, OS settings, etc. To do this, we will create a code, build the infrastructure for the test from it and will do the test. As a result, we get a flexible tool in the code to which you can attach any monitoring, and for which you don't have to pay a lot of money, because the environment is created in 7 minutes in an empty AWS account and destroyed after test