Brutal insert speed optimization by bypassing the ORM completely

app/Models/Proposal.php

@@ -193,11 +193,20 @@ class Proposal extends BaseModel
 
             // --- Insert new rows ---
             if ($changeset->newRows) {
-                $newRowData = [];
-                foreach ($changeset->newRows as $newRow) {
-                    $newRowData[] = new Row(['data' => $newRow]);
+                $conn = DB::connection();
+                $prepared = $conn->getPdo()->prepare('INSERT INTO rows (data) VALUES (?)');
+
+                foreach (array_chunk($changeset->newRows, 10000) as $i => $chunk) {
+                    $ids = [];
+                    foreach ($chunk as $newRow) {
+                        $prepared->execute([json_encode($newRow)]);
+                        $ids[] = $conn->getPdo()->lastInsertId();
+                    }
+
+                    $qms = rtrim(str_repeat('('.$newRevision->id.', ?),', count($ids)), ',');
+                    $conn->statement('INSERT INTO revision_row_pivot (revision_id, row_id) VALUES '.$qms.';',
+                        $ids);
                 }
-                $newRevision->rows()->saveMany($newRowData);
             }
 
             $newRevision->update(['row_count' => $newRevision->rows()->count()]);