FIX: Migration was only done for first batch (#344)

https://github.com/discourse/discourse-solved/pull/342 was deployed and observed to only have 5000 (batch size) migrated. This is an error in migration where the ids had a gap between the batch.

This PR changes the migration to just loop through all topic custom fields with each loop increasing by batch size.

db/migrate/20250318024953_copy_solved_topic_custom_field_to_discourse_solved_solved_topics.rb

@@ -3,12 +3,18 @@
 class CopySolvedTopicCustomFieldToDiscourseSolvedSolvedTopics < ActiveRecord::Migration[7.2]
   disable_ddl_transaction!
 
-  BATCH_SIZE = 5000
+  BATCH_SIZE = 10_000
 
   def up
+    max_id =
+      DB.query_single(
+        "SELECT MAX(id) FROM topic_custom_fields WHERE topic_custom_fields.name = 'accepted_answer_post_id'",
+      ).first
+    return unless max_id
+
     last_id = 0
-    loop do
+    while last_id < max_id
-      rows = DB.query(<<~SQL, last_id: last_id, batch_size: BATCH_SIZE)
+      DB.exec(<<~SQL, last_id: last_id, batch_size: BATCH_SIZE)
         INSERT INTO discourse_solved_solved_topics (
           topic_id,
           answer_post_id,
@@ -33,11 +39,10 @@ class CopySolvedTopicCustomFieldToDiscourseSolvedSolvedTopics < ActiveRecord::Mi
           AND ua.action_type = 15
         WHERE tc.name = 'accepted_answer_post_id'
           AND tc.id > :last_id
-        ORDER BY tc.topic_id, ua.created_at DESC
+          AND tc.id <= :last_id + :batch_size
-        LIMIT :batch_size
+        ON CONFLICT DO NOTHING
       SQL
 
-      break if rows.length == 0
       last_id += BATCH_SIZE
     end
   end

db/migrate/20250325074111_copy_remaining_solved_topic_custom_field_to_discourse_solved_solved_topics.rb

@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+#
+class CopyRemainingSolvedTopicCustomFieldToDiscourseSolvedSolvedTopics < ActiveRecord::Migration[
+  7.2
+]
+  disable_ddl_transaction!
+
+  BATCH_SIZE = 5000
+
+  def up
+    max_id =
+      DB.query_single(
+        "SELECT MAX(id) FROM topic_custom_fields WHERE topic_custom_fields.name = 'accepted_answer_post_id'",
+      ).first
+    return unless max_id
+
+    last_id = 0
+    while last_id < max_id
+      DB.exec(<<~SQL, last_id: last_id, batch_size: BATCH_SIZE)
+        INSERT INTO discourse_solved_solved_topics (
+          topic_id,
+          answer_post_id,
+          topic_timer_id,
+          accepter_user_id,
+          created_at,
+          updated_at
+        )
+        SELECT DISTINCT ON (tc.topic_id)
+          tc.topic_id,
+          CAST(tc.value AS INTEGER),
+          CAST(tc2.value AS INTEGER),
+          COALESCE(ua.acting_user_id, -1),
+          tc.created_at,
+          tc.updated_at
+        FROM topic_custom_fields tc
+        LEFT JOIN topic_custom_fields tc2
+          ON tc2.topic_id = tc.topic_id
+          AND tc2.name = 'solved_auto_close_topic_timer_id'
+        LEFT JOIN user_actions ua
+          ON ua.target_topic_id = tc.topic_id
+          AND ua.action_type = 15
+        WHERE tc.name = 'accepted_answer_post_id'
+          AND tc.id > :last_id
+          AND tc.id <= :last_id + :batch_size
+        ON CONFLICT DO NOTHING
+      SQL
+
+      last_id += BATCH_SIZE
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end