fix: migration for newly created self-hosting instances

packages/db/code-migrations/4-add-sessions.ts

@@ -100,6 +100,9 @@ async function createOldSessions() {
       if (!row || row.count === '0') {
         return null;
       }
+      if (row.created_at.startsWith('1970')) {
+        return null;
+      }
       return new Date(row.created_at);
     } catch (e) {
       return defaultDate;

packages/db/code-migrations/8-order-keys.ts

@@ -139,7 +139,10 @@ export async function up() {
   const firstEventDateJson = await firstEventDateResponse.json<{
     created_at: string;
   }>();
-  if (firstEventDateJson[0]?.created_at) {
+  if (
+    firstEventDateJson[0]?.created_at &&
+    !firstEventDateJson[0]?.created_at.startsWith('1970')
+  ) {
     const firstEventDate = new Date(firstEventDateJson[0]?.created_at);
     // Step 2: Copy data from old tables to new tables (partitioned by month for efficiency)
     // Set endDate to first of next month to ensure we capture all data in the current month
@@ -174,7 +177,10 @@ export async function up() {
     created_at: string;
   }>();
 
-  if (firstSessionDateJson[0]?.created_at) {
+  if (
+    firstSessionDateJson[0]?.created_at &&
+    !firstSessionDateJson[0]?.created_at.startsWith('1970')
+  ) {
     const firstSessionDate = new Date(
       firstSessionDateJson[0]?.created_at ?? '',
     );