On 2019-05-22 05:39, Jonathan S. Katz wrote:
Speaking of feedback, please provide me with your feedback on the technical correctness of this announcement so I can incorporate changes prior to the release.
Here are a few changes.Main change: generated columns exist only in the STORED variety. VIRTUAL will hopefully later be added.
thanks, Erik Rijkers
--- 12beta1.md.orig 2019-05-22 06:33:16.286099932 +0200 +++ 12beta1.md 2019-05-22 06:48:24.279966057 +0200 @@ -30,12 +30,12 @@ Additionally, PostgreSQL 12 adds the ability to rebuild indexes concurrently, which lets you perform a [`REINDEX`](https://www.postgresql.org/docs/devel/sql-reindex.html) operation without blocking any writes to the index. The inclusion of this feature should -help with length index rebuilds that could cause potential downtime evens when -administration a PostgreSQL database in a production environment. +help with lengthy index rebuilds that could cause potential downtime when +administrating a PostgreSQL database in a production environment. PostgreSQL 12 extends the abilities of several of the specialized indexing mechanisms. The ability to create covering indexes, i.e. the `INCLUDE` clause -that was introduced in PostgreSQL 11, have now been added to GiST indexes. +that was introduced in PostgreSQL 11, has now been added to GiST indexes. SP-GiST indexes now support the ability to perform K-nearest neighbor (K-NN) queries for data types that support the distance (`<->`) operation. @@ -49,7 +49,7 @@ Common table expressions (aka `WITH` queries) can now be automatically inlined in a query if they are a) not recursive, b) do not have any side-effects and -c) are only referenced once in a later part of a query. These removes a known +c) are only referenced once in a later part of a query. This removes a known "optimization fence" that has existed since the introduction of the `WITH` clause in PostgreSQL 8.4 @@ -88,7 +88,7 @@ PostgreSQL 12 now supports case-insensitive and accent-insensitive collations for ICU provided collations, also known as "[nondeterministic collations](https://www.postgresql.org/docs/devel/collation.html#COLLATION-NONDETERMINISTIC)". When used, these collations can provide convenience for comparisons and sorts, -but can also lead to a performance penalty depending as a collation may need to +but can also lead to a performance penalty as a collation may need to make additional checks on a string. ### Most-common Value Statistics @@ -102,10 +102,9 @@ PostgreSQL 12 lets you create [generated columns](https://www.postgresql.org/docs/devel/ddl-generated-columns.html) that compute their values based on the contents of other columns. This feature -provides two types of generated columns: - -- Stored generated columns, which are computed on inserts and updated and are saved on disk -- Virtual generated columns, which are computed only when a column is read as part of a query +provides only one type of generated column: Stored generated columns, which are computed on inserts +and updated and are saved on disk. Virtual generated columns (computed only when a column +is read as part of a query) are not yet implemented. ### Pluggable Table Storage Interface @@ -128,7 +127,7 @@ ### Authentication -GSSAPI now supports client and server-side encryption and can be specified in +GSSAPI now supports client- and server-side encryption and can be specified in the [`pg_hba.conf`](https://www.postgresql.org/docs/devel/auth-pg-hba-conf.html) file using the `hostgssenc` and `hostnogssenc` record types. PostgreSQL 12 also allows for LDAP servers to be discovered based on `DNS SRV` records if
