On 7th of April, Teodor Sigaev committed patch:
Phrase full text search.
Patch introduces new text search operator (<-> or <DISTANCE>) into tsquery.
On-disk and binary in/out format of tsquery are backward compatible.
It has two side effect:
- change order for tsquery, so, users, who has a btree index over tsquery,
should reindex it
- less number of parenthesis in tsquery output, and tsquery becomes more
Authors: Teodor Sigaev, Oleg Bartunov, Dmitry Ivanov
Reviewers: Alexander Korotkov, Artur Zakirov
Continue reading Waiting for 9.6 – Phrase full text search.
On 2nd of September, Teodor Sigaev committed patch:
Allow usage of huge maintenance_work_mem for GIN build.
Currently, in-memory posting list during GIN build process is limited 1GB
because of using repalloc. The patch replaces call of repalloc to repalloc_huge.
It increases limit of posting list from 180 millions
(1GB / sizeof(ItemPointerData)) to 4 billions limited by maxcount/count fields
in GinEntryAccumulator and subsequent calls. Check added.
Also, fix accounting of allocatedMemory during build to prevent integer
overflow with maintenance_work_mem > 4GB.
Robert Abraham <firstname.lastname@example.org> with additions by me
Continue reading Waiting for 9.6 – Allow usage of huge maintenance_work_mem for GIN build.
Today, I'd like to show you how you can use the same index for two different types of conditions. One that is using normal BTree indexing ( equal, less than, greater than ), and one that is using GIN/GiST index, for full text searching.
Continue reading Joining BTree and GIN/GiST indexes
On 23rd of March, Andrew Dunstan committed patch:
Introduce jsonb, a structured format for storing json.
The new format accepts exactly the same data as the json type. However, it is
stored in a format that does not require reparsing the orgiginal text in order
to process it, making it much more suitable for indexing and other operations.
Insignificant whitespace is discarded, and the order of object keys is not
preserved. Neither are duplicate object keys kept - the later value for a given
key is the only one stored.
The new type has all the functions and operators that the json type has,
with the exception of the json generation functions (to_json, json_agg etc.)
and with identical semantics. In addition, there are operator classes for
hash and btree indexing, and two classes for GIN indexing, that have no
equivalent in the json type.
This feature grew out of previous work by Oleg Bartunov and Teodor Sigaev, which
was intended to provide similar facilities to a nested hstore type, but which
in the end proved to have some significant compatibility issues.
Authors: Oleg Bartunov, Teodor Sigaev, Peter Geoghegan and Andrew Dunstan.
Review: Andres Freund
Continue reading Waiting for 9.4 – Introduce jsonb, a structured format for storing json.
On 1st of February, Tom Lane committed patch:
Support LIKE and ILIKE index searches via contrib/pg_trgm indexes.
Unlike Btree-based LIKE optimization, this works for non-left-anchored
search patterns. The effectiveness of the search depends on how many
trigrams can be extracted from the pattern. (The worst case, with no
trigrams, degrades to a full-table scan, so this isn't a panacea. But
it can be very useful.)
Alexander Korotkov, reviewed by Jan Urbanski
Continue reading Waiting for 9.1 – Faster LIKE/ILIKE
Today we have two interesting patches:
- patch by Teodor Sigaev and Oleg Bartunov, and committed by Tom Lane, which adds interesting capability to GIN indexes
- patch by Zoltan Boszormenyi, also committed by Tom, which adds “RESTART" option to ALTER SEQUENCE. With some interesting consequences
Continue reading Waiting for 8.4 – partial-match support in GIN, and sequence restart