https://github.com/bonfire-networks/bonfire-app/issues/765

flavours/classic/repo/migrations/20240108094945_gin_indexes.exs

@@ -0,0 +1,37 @@
+defmodule Bonfire.Repo.Migrations.GinIndexes do
+  use Ecto.Migration
+
+  @disable_ddl_transaction true
+  @disable_migration_lock true
+  # ^ Needed to migrate indexes concurrently. 
+  # Disabling DDL transactions removes the guarantee that all of the changes in the migration will happen at once. 
+  # Disabling the migration lock removes the guarantee only a single node will run a given migration if multiple nodes are attempting to migrate at the same time.
+
+  def up do
+    execute "CREATE EXTENSION IF NOT EXISTS pg_trgm;"
+
+    create_index("bonfire_data_identity_character", "username")
+    create_index("bonfire_data_social_profile", "name")
+
+    create_index_fields(
+      "bonfire_data_social_post_content",
+      "name gin_trgm_ops, summary gin_trgm_ops, html_body gin_trgm_ops"
+    )
+  end
+
+  def down do
+    # TODO
+  end
+
+  def create_index(table, field) do
+    create_index_fields(table, "#{field} gin_trgm_ops")
+  end
+
+  def create_index_fields(table, fields) do
+    execute """
+      CREATE INDEX CONCURRENTLY #{table}_gin_index 
+        ON #{table} 
+        USING gin (#{fields});
+    """
+  end
+end