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In the big data era, data is one of the most valuable assets for enterprises. The ultimate goal of data analytics is to power swift, agile business decision making. As database technologies advance at a breathtaking pace in recent years, a large number of excellent database systems have emerged. Some of them are impressive in wide-table queries but do not work well in complex queries. Some support flexible multi-table queries but are held back by slow query speed.

Each type of data has a data model that best represents them. However, in real business scenarios, there is no such thing as ultra-fast data analytics under the perfect data model. Big data engineers sometimes have to make compromises on data models. Such compromises may cause long latency in complex queries or damage the real-time query performance because engineers must take the trouble to convert complex data models into flat tables.

New business requirements put forward new challenges for database systems. A good OLAP database system must be able to deliver excellent performance in both wide-table and multi-table scenarios. This system must also reduce the workload of big data engineers and enable customers to query data of any dimension in real time without worrying about data construction.

Apache Druid has been a staple for real-time analytics. However, with evolving and sophisticated analytics demands, it has faced challenges in satisfying modern data performance needs. Enter StarRocks, a high-performance, open-source analytical database, designed to adeptly meet the advanced analytics needs of contemporary enterprises by offering robust capabilities and performance.

In this article, we’ll explore the functionalities, strengths, and challenges of both Apache Druid and StarRocks. Using practical examples and benchmark results, we aim to guide you in identifying which database might best meet your data needs.

Migration from Oracle to vanilla PostgreSQL hits roadblocks with packages, autonomous transactions, and collections—they simply don’t exist there. We’ll break down why ora2pg stumbles, how native implementations of these mechanisms in Postgres Pro Enterprise make life easier, and how ora2pgpro translates PL/SQL semantically correctly, without hacks or crude regex.

September 25th marks the release of PostgreSQL 18. This article covers the March CommitFest and concludes the series covering the new features of the upcoming update. This article turned out quite large, as the last March CommitFest is traditionally the biggest and richest in new features.

You can find previous reviews of PostgreSQL 18 CommitFests here: 2024-07, 2024-09, 2024-11, 2025-01.

Filename Extension: .6nf

6NF File Format is a new bitemporal, sixth-normal-form (6NF)-inspired data exchange format designed for DWH and for reporting. It replaces complex hierarchical formats like XBRL, XML, JSON, and YAML

pg_stat_statements is the standard PostgreSQL extension used to track query statistics: number of executions, total and average execution time, number of returned rows, and other metrics. This information allows to analyze query behavior over time, identify problem areas, and make informed optimization decisions. However, in systems with high contention, pg_stat_statements itself can become a bottleneck and cause performance drops. In this article, we will analyze in which scenarios the extension becomes a source of problems, how sampling is structured, and in which cases its application can reduce overhead.

Would you like to know which indexes are used frequently or rarely? Which ones aren't used at all? Which tables and indexes are the largest? It's very easy to create visualizations for this. They're both visually appealing and practically useful.

DBAs often struggle to identify the most resource-hungry processes that degrade system performance. Back in 2017, DBA — and now Postgres Professional engineer — Andrey Zubkov faced the same challenge. This led him to develop pg_profile for PostgreSQL, which has since evolved into pgpro_pwr.

In this article, we’ll dive into strategic database monitoring and show you how to pinpoint bottlenecks in your databases using our tools.

We continue to follow the news about PostgreSQL 18. The January CommitFest brings in some notable improvements to monitoring, as well as other new features.

You can find previous reviews of PostgreSQL 18 CommitFests here: 2024-07, 2024-09, 2024-11.

According to Gartner, natural language queries will replace SQL as early as 2026. 

While Gartner's prediction may be optimistic, the shift toward natural language interfaces for databases is inevitable. The timeline may vary, but the transition itself is a certainty.

We continue the series of articles about new patches coming to PostgreSQL 18, this one covering the news of the November CommitFest.

If you missed the previous reviews, you can check them out here: 2024-07, 2024-09.

If your code has many nested executions of stored procedures, you can benefit from building popular "flame diagram" of the execution time which is de facto standard for performance profiling.

Statistically, September CommitFests feature the fewest commits. Apparently, the version 18 CommitFest is an outlier. There are many accepted patches and many interesting new features to talk about.

If you missed the July CommitFest, get up to speed here: 2024-07.

When we go abroad for vacation or meet a foreigner on the street who doesn’t speak Russian but is trying to ask, “Where is the restroom? How do I get to…”, we wonder how to explain things to them in Russian in a way they would understand.

I asked myself a similar question when trying to explain something to a colleague using SQL while they were working with Java. The main goal of my work was to create a quality test model. Without it, there would be no proper regression testing later on.

I started by building a framework filling it with test cases. We held a meeting where we discussed priority of positive and negative test cases briefly. When developing the test scenarios, I used the incremental model, but as practice showed, this approach also required an iterative method. For example, it is like having the outline of the Mona Lisa first, then adding colors, painting the background, and so on.

It’s better to maintain the checklist in Excel format to add columns, write notes, and more. And let’s not forget that, as we take on the role of Leonardo da Vinci, we use different colors and get creative.

I am a manager by profession specializating in Production Management. My motivator is the Theory of Constraints (TOC) methodology, which focuses on identifying and managing the key constraint of a system to determine the efficiency of the entire system as a whole:

This article is the first in the series about the upcoming PostgreSQL 18 release. Let us take a look at the features introduced in the July CommitFest.

Planner: Hash Right Semi Join support
Planner: materializing an internal row set for parallel nested loop join
Planner support functions for generate_series
EXPLAIN (analyze): statistics for Parallel Bitmap Heap Scan node workers
Functions min and max for composite types
Parameter names for regexp* functions
Debug mode in pgbench
pg_get_backend_memory_contexts: column path instead of parent, new column type
Function pg_get_acl
pg_upgrade: pg_dump optimization
Predefined role pg_signal_autovacuum_worker

Since the PostgreSQL 17 RC1 came out, we are on a home run towards the official PostgreSQL release, scheduled for September 26, 2024.

Let's take a look at the patches that came in during the March CommitFest.

Spring is in full swing as we bring you the hottest winter news of the January Commitfest. Let's get to the good stuff right away!

Previous articles about PostgreSQL 17: 2023-07, 2023-09, 2023-11.

In the evolving landscape of database technology, choosing the right database management system is crucial for the efficiency and scalability of applications. This article presents a detailed comparison of the performance between Microsoft's CosmosDB and MS SQL Server. We'll examine how each database performs under various load conditions and share some interesting findings.

The November commitfest is ripe with new interesting features! Without further ado, let's proceed with the review.

If you missed our July and September commitfest reviews, you can check them out here: 2023-07, 2023-09.

ON LOGIN trigger
Event triggers for REINDEX
ALTER OPERATOR: commutator, negator, hashes, merges
pg_dump --filter=dump.txt
psql: displaying default privileges
pg_stat_statements: track statement entry timestamps and reset min/max statistics
pg_stat_checkpointer: checkpointer process statistics
pg_stats: statistics for range type columns
Planner: exclusion of unnecessary table self-joins
Planner: materialized CTE statistics
Planner: accessing a table with multiple clauses
Index range scan optimization
dblink, postgres_fdw: detailed wait events
Logical replication: migration of replication slots during publisher upgrade
Replication slot use log
Unicode: new information functions
New function: xmltext
AT LOCAL support
Infinite intervals
ALTER SYSTEM with unrecognized custom parameters
Building the server from source

We continue to follow the news of the PostgreSQL 17 development. Let's find out what the September commitfest brings to the table.

If you missed our July commitfest review, you can check it out here: 2023-07.

Removed the parameter old_snapshot_threshold
New parameter event_triggers
New functions to_bin and to_oct
New system view pg_wait_events
EXPLAIN: a JIT compilation time counter for tuple deforming
Planner: better estimate of the initial cost of the WindowAgg node
pg_constraint: NOT NULL constraints
Normalization of CALL, DEALLOCATE and two-phase commit control commands
unaccent: the target rule expressions now support values in quotation marks
COPY FROM: FORCE_NOT_NULL * and FORCE_NULL *
Audit of connections without authentication
pg_stat_subscription: new column worker_type
The behaviour of pg_promote in case of unsuccessful switchover to a replica
Choosing the disk synchronization method in server utilities
pg_restore: optimization of parallel recovery of a large number of tables
pg_basebackup and pg_receivewal with the parameter dbname
Parameter names for a number of built-in functions
psql: \watch min_rows