MinervaDB Blog: Mastering WebScale Database Infrastructure

PostgreSQL “as of” queries: How to Implement Them

In PostgreSQL, you can implement “as of” queries using the SQL standard’s temporal query features, which allow you to query a table as it existed at a specific point in time. There are two main […]

PostgreSQL Slow Query: How to Compute Its Cost

The cost of a slow query in PostgreSQL can be estimated by the Query Planner, which uses statistics about the data in the tables being queried to make predictions about the query execution time. The […]

PostgreSQL Optimizer Plan: How Plan Stability Works

In PostgreSQL, optimizer plan stability is a feature that allows the query planner to reuse a previously cached query plan for a SQL statement instead of generating a new plan. This can improve query performance […]

PostgreSQL Global Indexes: How They Are Implemented

In PostgreSQL, global indexes are implemented using a shared-nothing architecture, which means that the index data is partitioned and distributed across multiple physical nodes or “shards.” This allows for parallel query processing and improved performance […]

MyRocks Bloom Filter: How It Works

Bloom filters are probabilistic data structures that are used for membership tests. They are particularly useful in databases as they allow faster and more efficient querying of data. In MyRocks, a storage engine based on […]

PostgreSQL synchronous_commit and Synchronous Standby Replication: How to Implement

PostgreSQL provides the option of synchronous replication to ensure that transactions are committed on the standby servers before they are acknowledged as being committed on the primary server. This can provide an added level of […]

Disk I/O MySQL: Explaining Higher Than Expected I/O on Hot Tables

MySQL Hot Tables are tables that experience a high volume of traffic and activity, and can quickly become a bottleneck for database performance. When you see higher than expected disk I/O on MySQL Hot Tables, […]

Avoid PostgreSQL Mutating Table: How to Prevent It

In PostgreSQL, a mutating table error occurs when a row-level trigger tries to modify the same table that the trigger is defined on. This occurs because the database does not allow a query to modify […]

PostgreSQL Materialised Views: How They Work

Materialized views in PostgreSQL are useful when you have frequently used queries that are complex, slow, or involve large amounts of data. In such cases, creating a materialized view can significantly improve query performance. A […]

How to prevent Replication Break in MySQL while adding INDEX/COLUMN using PT-OSC (pt-online-schema-change)?

When adding indexes or columns in MySQL, it is important to be aware of the potential for replication to break. One way to prevent this is to use a tool like pt-online-schema-change from the Percona […]