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Author: akorotkov

README.hstore_ops

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+hstore_ops - better operator class for hstore
+=============================================
+
+hstore_ops extension provides another implementation of GIN index (opclass)
+for hstore. It provides smaller index and faster @> operator queries than
+default GIN opclass. However, queries containing ?, ?|, ?& operators could
+become a little slower.
+    
+Idea of this opclass is to use composite GIN key which consists of hashes
+of hstore key and value. Thus, search for @> operator is possible as simple
+match for each queried key-value pair. Search for @>, ?, ?|, ?& is possible
+as partial match for each queried hstore key. Recheck is essential for
+every kind of search, because of possible hash collision. Hashing provides
+small size of index, mixing key and value into same GIN key provides high
+performance for @> search operator.
+
+Authors
+-------
+
+ * Alexander Korotkov <[email protected]>, Intaro Soft Ltd., Moscow, Russia
+ * Oleg Bartunov <[email protected]>, Moscow University, Moscow, Russia
+
+License
+-------
+
+Development version, available on github, released under the
+GNU General Public License, version 2 (June 1991).
+
+Downloads
+---------
+
+    Stable version of hstore_ops is available from
+    https://github.com/akorotkov/hstore_ops
+
+Installation
+------------
+
+hstore_ops is regular PostgreSQL extension depending on hstore contrib.
+To build and install it you should ensure in following:
+    
+ * You have development package of PostgreSQL installed or you built
+   PostgreSQL from source.
+ * Your PATH variable configured so that pg_config command available.
+ * You did "CREATE EXTENSION hstore;" before "CREATE EXTENSION hstore_ops;".
+    
+Typical installation procedure may look like this:
+    
+    $ git clone https://github.com/akorotkov/hstore_ops.git
+    $ cd hstore_ops
+    $ make USE_PGXS=1
+    $ sudo make USE_PGXS=1 install
+    $ make USE_PGXS=1 installcheck
+    $ psql DB -c "CREATE EXTENSION hstore_ops;"
+
+Usage
+-----
+
+Just create index on hstore column using following command.
+   
+    CREATE INDEX index_name ON table_name USING GIN (column_name gin_hstore_hash_ops);
+    
+Index will be automatically used for search on @>, ?, ?|, ?& operators on this
+column.