This hack backports a phpBB 3 feature that optimizes the phpBB search indexing. Certain queries in the search indexing process that triggers on posting will manually count the number of times words appear in the phpbb_search_wordmatch database table every time a new post is created. This may cause slow down when posting on very large boards, as the queries may need to examine hundreds of thousands or millions of rows.
As a work around, this hack adds a column to the search_wordlist database table to hold that count for each word. The queries that were manually counting are rewritten to use the stored count to increase their performance and speed. The stored count is updated when new posts are made.
This hack is seamlessly supported by Word Cleaner, which will look for the stored count facility and use it instead of manually counting word occurrences.
An included optional add-on also provides support for rebuilding the search engine index using the Database Maintenance hack by Philipp Kordowich.