#Article
Recent posts
December 31, 2022
  •  
PostgreSQL
We continue to follow the news of the upcoming PostgreSQL 16. The third CommitFest concluded in early December. Let's look at the results.
If you missed the previous CommitFests, check out our reviews: 2022-07 , 2022-09 .
Here are the patches I want to talk about:
meson: a new source code build system
Documentation: a new chapter on transaction processing
psql: \d+ indicates foreign partitions in a partitioned table
psql: extended query protocol support
Predicate locks on materialized views
Tracking last scan time of indexes and tables
pg_buffercache: a new function pg_buffercache_summary
walsender displays the database name in the process status
Reducing the WAL overhead of freezing tuples
Reduced power consumption when idle
postgres_fdw: batch mode for COPY
Modernizing the GUC infrastructure
Hash index build optimization
MAINTAIN ― a new privilege for table maintenance
SET ROLE: better role change management
Support for file inclusion directives in pg_hba.conf and pg_ident.conf
Regular expressions support in pg_hba.conf
November 14, 2022
  •  
PostgreSQL
It’s official! PostgreSQL 15 is out, and the community is abuzz discussing all the new features of the fresh release.
Meanwhile, the October CommitFest for PostgreSQL 16 had come and gone, with its own notable additions to the code.
If you missed the July CommitFest, our previous article will get you up to speed in no time.
Here are the patches I want to talk about:
SYSTEM_USER function
Frozen pages/tuples information in autovacuum's server log
pg_stat_get_backend_idset returns the actual backend ID
Improved performance of ORDER BY / DISTINCT aggregates
Faster bulk-loading into partitioned tables
Optimized lookups in snapshots
Bidirectional logical replication
pg_auth_members: pg_auth_members: role membership granting management
pg_auth_members: role membership and privilege inheritance
pg_receivewal and pg_recvlogical can now handle SIGTERM
October 6, 2022
  •  
PostgreSQL

Queries in PostgreSQL: 7. Sort and merge
In the previous articles, covered query execution stages , statistics , sequential and index scan , and two of the three join methods: nested loop and hash join . This last article of the series will cover the merge algorithm and sorting . I will also demonstrate how the three join methods compare against each other.
August 17, 2022
  •  
PostgreSQL
August is a special month in PostgreSQL release cycle. PostgreSQL 15 isn't even officially out yet, but the first CommitFest for the 16th release has already been held.
Let's compile the server and check out the cool new stuff!
August 11, 2022
  •  
PostgreSQL
So far we have covered query execution stages , statistics , sequential and index scan , and have moved on to joins.
The previous article focused on the nested loop join , and in this one I will explain the hash join . I will also briefly mention group-bys and distincs.
July 5, 2022
  •  
PostgreSQL
So far we've discussed query execution stages , statistics , and the two basic data access methods: Sequential scan and Index scan .
The next item on the list is join methods. This article will remind you what logical join types are out there, and then discuss one of three physical join methods, the Nested loop join. Additionally, we will check out the row memoization feature introduced in PostgreSQL 14.
Joins
Joins are the primary feature of SQL, the foundation that enables its power and agility. Sets of rows (whether pulled directly from a table or formed as a result of an operation) are always joined together in pairs. There are several types of joins.
...