Mastering PostgreSQL 9.6

Defining GIN indexes

If you want to apply text search to a column or a group of columns, there are basically two choices:

• Create a functional index using GIN
• Add a column containing ready to use tsvectors and a trigger to keep them in sync

In this section, both options will be outlines. To show how things work, I have created some sample data:

test=# CREATE TABLE t_fts AS SELECT comment FROM pg_available_extensions;SELECT 43

Indexing the column directly with a functional index is definitely a slower but more space-efficient way to get things done:

test=# CREATE INDEX idx_fts_func ON t_fts USING gin(to_tsvector('english', comment)); CREATE INDEX

Deploying an index on the function is easy but it can lead to some overhead. Adding a materialized ...