On 9th of November 2017, Robert Haas committed patch: Add hash partitioning. Hash partitioning is useful when you want to partition a growing data set evenly. This can be useful to keep table sizes reasonable, which makes maintenance operations such as VACUUM faster, ...

For a long time hash indexed were not crash safe, and couldn't be used on replication slave, because they skipped WAL. Now, thanks to these two commits, it has changed: On 14th of March 2017, Robert Haas committed patch: hash: Add write-ahead ...

In previous post in the series I wrote about how to interpret single line in explain analyze output, it's structure, and later on described all basic data-getting operations (nodes in explain tree). Today, we'll move towards more complicated operations.

On 18th of February, Alvaro Herrera committed patch: Convert Postgres arrays to Perl arrays on PL/perl input arguments More generally, arrays are turned in Perl array references, and row and composite types are turned into Perl hash references. This is done recursively, ...

Today, Mattias|farm on IRC asked how to create primary key using HASH index. After some talk, he said that in some books it said that for "=" (equality) hash indexes are better. So, I digged a bit deeper.