From ed987ff6d7816cb7e1c4cfeb7f111c12a67aeec2 Mon Sep 17 00:00:00 2001 From: "Jonathan S. Katz" Date: Mon, 2 Sep 2019 11:12:29 -0400 Subject: [PATCH] Updated draft for PG12 press release per community feedback. --- releases/12/en/release.en.md | 50 ++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 19 deletions(-) diff --git a/releases/12/en/release.en.md b/releases/12/en/release.en.md index 55f5ab3..f8d1ba2 100644 --- a/releases/12/en/release.en.md +++ b/releases/12/en/release.en.md @@ -21,7 +21,7 @@ PostgreSQL benefits from over 20 years of open source development and has become the preferred open source relational database for organizations of all sizes. The project continues to receive recognition across the industry, including being featured for the second year in a row as the "DBMS of the Year" in 2018 by -DB-Engines and receiving the "Lifetime Achievement" open source award at OSCon +DB-Engines and receiving the "Lifetime Achievement" open source award at OSCON 2019. ## Overall Performance Improvements @@ -37,15 +37,23 @@ in query performance. Queries on partitioned tables have also seen demonstrable improvements, particularly for tables with thousands of partitions that only need to retrieve -data from a select few. PostgreSQL 12 also improvements the performance of -adding data to partitioned tables via "INSERT" and "COPY", and a new partition -can be attached to a table with blocking any queries on it. +data from a limited subset. PostgreSQL 12 also improves the performance of +adding data to partitioned tables with "INSERT" and "COPY", and includes the +ability to attach a new partition to a table without blocking queries. There are additional enhancements to indexing in PostgreSQL 12 that affect -overall performance, including lower overhead in write-head-log generation for +overall performance, including lower overhead in write-ahead log generation for GiST, GIN, and SP-GiST indexes, the ability to create covering indexes (the -"INCLUDE" clause) on GiST indexes, and the ability to perform K-nearest -neighbor queries with the distance operator ("<->") using SP-GiST indexes. +"INCLUDE" clause) on GiST indexes, the ability to perform K-nearest +neighbor queries with the distance operator ("<->") using SP-GiST indexes, and +CREATE STATISTICS now supporting most-common value (MCV) statistics to help with +columns that are nonuniformly distributed. + +Just-in-time (JIT) compilation using LLVM, introduced in PostgreSQL 11, is now +enabled by default. JIT compilation can provide performance benefits +to the execution of expressions in WHERE clauses, target lists, aggregates, +and some internal operations, and is available if your PostgreSQL installation +is compiled or packaged with LLVM. ## Enhancements to SQL Conformance & Functionality @@ -55,9 +63,9 @@ features that build on the implementation of the SQL standard and offer enhanced functionality. PostgreSQL 12 introduces the ability to run queries over JSON documents using -JSON path expressions defined in the SQL/JSON standard. Additionally, certain -JSON path expressions can utilize the existing indexing mechanisms for documents -stored in the JSONB format to efficiently retrieve data. +JSON path expressions defined in the SQL/JSON standard. Such queries may utilize +the existing indexing mechanisms for documents stored in the JSONB format to +efficiently retrieve data. Common table expressions, aka "WITH" queries, can now be automatically inlined by PostgreSQL 12, which in turn can help increase the performance of many @@ -65,10 +73,10 @@ existing queries. In this release, a WITH query can be inlined if it is not recursive, does not have any side-effects, and is only referenced once in a later part of a query. -PostgreSQL 12 also introduces generated columns, which is a type of column that -can be computed its value from other columns in the same table. Currently, -PostgreSQL only supports "stored generated columns," where the computed value is -stored on the disk. +PostgreSQL 12 introduces "generated columns." Defined in the SQL standard, this +type of column computes its value from the contents of other columns in the same +table. In this version, PostgreSQL supports "stored generated columns," where +the computed value is stored on the disk. ## Internationalization @@ -79,13 +87,13 @@ accent-insensitive comparisons. ## Authentication PostgreSQL expands on its robust authentication method support with several -enhancements that provide additional security and functionality in -PostgreSQL 12. This release introduces both client and server-side encryption -for authentication over GSSAPI interfaces, as well as the ability for PostgreSQL -to discover LDAP servers using if it was compiled with OpenLDAP. +enhancements that provide additional security and functionality. This release +introduces both client and server-side encryption for authentication over GSSAPI +interfaces, as well as the ability for PostgreSQL to discover LDAP servers if +PostgreSQL is compiled with OpenLDAP. Additionally, PostgreSQL 12 now supports a form of multifactor authentication. A -PostgreSQL server can now require an authentication client to provide a valid +PostgreSQL server can now require an authenticating client to provide a valid SSL certificate with their username using the "clientcert=verify-full" option and combine this with the requirement of a separate authentication method (e.g. "scram-sha-256"). @@ -101,6 +109,10 @@ offline cluster using the "pg_checksums" command. Previously page checksums, a feature to help verify the integrity of data stored to disk, could only be enabled at the time a PostgreSQL cluster was initialized with "initdb." +PostgreSQL 12 also introduces progress reporting statistics for the +"CREATE INDEX", "REINDEX", "CLUSTER", and "VACUUM FULL", operations, and to the +"pg_checksums" command via the "--progress" flag. + For a full list of features included in this release, please read the release notes, which can be found at: https://www.postgresql.org/docs/12/static/release-12.html -- 2.39.5