Add full text search support using TSV indexes

example/db/migrate/20190405042247_add_search_column.rb

@@ -0,0 +1,33 @@
+class AddSearchColumn < ActiveRecord::Migration[5.1]
+  def self.up
+    add_column :products, :tsv, :tsvector
+    add_index :products, :tsv, using: "gin"
+
+    say_with_time("Adding trigger to update the ts_vector column") do
+      execute <<-SQL
+        CREATE FUNCTION products_tsv_trigger() RETURNS trigger AS $$
+        begin
+          new.tsv :=
+          setweight(to_tsvector('pg_catalog.english', coalesce(new.name,'')), 'A') ||
+          setweight(to_tsvector('pg_catalog.english', coalesce(new.description,'')), 'B');
+          return new;
+        end
+        $$ LANGUAGE plpgsql;
+
+        CREATE TRIGGER tsvectorupdate BEFORE INSERT OR UPDATE ON products FOR EACH ROW EXECUTE PROCEDURE products_tsv_trigger();
+        SQL
+      end
+  end
+
+  def self.down
+    say_with_time("Removing trigger to update the tsv column") do
+      execute <<-SQL
+        DROP TRIGGER tsvectorupdate
+        ON products
+        SQL
+    end
+
+    remove_index :products, :tsv
+    remove_column :products, :tsv
+  end
+end