From 912801a34951a77bbfc56d1d69bd4fc8b106423b Mon Sep 17 00:00:00 2001
From: TheNEwmanator15 <3686761+Thenewmanator15@users.noreply.github.com>
Date: Fri, 25 Sep 2026 00:11:48 +0100
Subject: [PATCH] Load creators and primary data with less per-row work

- _loadCreators(): read columns by index in onRow as rows arrive instead of
  materializing every item/creator row as a Proxy, whose property reads
  each go through getResultByName()
- _loadPrimaryData(): compute the column list and ID column once per query
  rather than once per row
- ItemFields._getLoadInfo(): index the cache with arrays instead of a Map

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 .../content/zotero/xpcom/data/dataObjects.js  |  7 +-
 .../content/zotero/xpcom/data/itemFields.js   |  6 +-
 chrome/content/zotero/xpcom/data/items.js     | 75 ++++++++++---------
 3 files changed, 48 insertions(+), 40 deletions(-)

diff --git a/chrome/content/zotero/xpcom/data/dataObjects.js b/chrome/content/zotero/xpcom/data/dataObjects.js
index 3e5726602d..414d438f05 100644
--- a/chrome/content/zotero/xpcom/data/dataObjects.js
+++ b/chrome/content/zotero/xpcom/data/dataObjects.js
@@ -555,14 +555,17 @@ Zotero.DataObjects.prototype._loadPrimaryData = async function (libraryID, ids,
 		sql += ' AND O.' + this._ZDO_id + ' IN (' + ids.join(',') + ')';
 	}
 	
+	var columns = Object.keys(this._primaryDataSQLParts);
+	var idColumn = columns.indexOf(this._ZDO_id);
 	await Zotero.DB.queryAsync(
 		sql,
 		params,
 		{
 			noCache: true,
 			onRow: function (row) {
-				var id = row.getResultByName(this._ZDO_id);
-				var columns = Object.keys(this._primaryDataSQLParts);
+				var id = idColumn != -1
+					? row.getResultByIndex(idColumn)
+					: row.getResultByName(this._ZDO_id);
 				var rowObj = {};
 				for (let i=0; i<columns.length; i++) {
 					rowObj[columns[i]] = row.getResultByIndex(i);
diff --git a/chrome/content/zotero/xpcom/data/itemFields.js b/chrome/content/zotero/xpcom/data/itemFields.js
index a884fe6dbe..febd0abe8f 100644
--- a/chrome/content/zotero/xpcom/data/itemFields.js
+++ b/chrome/content/zotero/xpcom/data/itemFields.js
@@ -154,9 +154,9 @@ Zotero.ItemFields = new function () {
 		}
 		var byField = _loadInfo[itemTypeID];
 		if (!byField) {
-			byField = _loadInfo[itemTypeID] = new Map();
+			byField = _loadInfo[itemTypeID] = [];
 		}
-		var info = byField.get(fieldID);
+		var info = byField[fieldID];
 		if (info === undefined) {
 			if (!this.getID(fieldID)) {
 				info = false;
@@ -171,7 +171,7 @@ Zotero.ItemFields = new function () {
 					isISBN: resolvedID == this.getID('ISBN')
 				};
 			}
-			byField.set(fieldID, info);
+			byField[fieldID] = info;
 		}
 		return info;
 	};
diff --git a/chrome/content/zotero/xpcom/data/items.js b/chrome/content/zotero/xpcom/data/items.js
index f98b5eadcc..ff6c9f434c 100644
--- a/chrome/content/zotero/xpcom/data/items.js
+++ b/chrome/content/zotero/xpcom/data/items.js
@@ -404,7 +404,6 @@ Zotero.Items = function () {
 			+ 'FROM items LEFT JOIN itemCreators USING (itemID) '
 			+ 'WHERE libraryID=?' + idSQL + " ORDER BY itemID, orderIndex";
 		var params = [libraryID];
-		var rows = await Zotero.DB.queryAsync(sql, params, { noCache: true });
 		
 		// Mark creator indexes above the number of creators as changed,
 		// so that they're cleared if the item is saved
@@ -425,46 +424,52 @@ Zotero.Items = function () {
 		var item;
 		var index = 0;
 		var maxOrderIndex = -1;
-		for (let i = 0; i < rows.length; i++) {
-			let row = rows[i];
-			let itemID = row.itemID;
-			
-			if (itemID != lastItemID) {
-				if (!this._objectCache[itemID]) {
-					throw new Error("Item " + itemID + " not loaded");
-				}
-				item = this._objectCache[itemID];
+		// Read columns by index as rows arrive, rather than building a Proxy row
+		// object for every item/creator pair
+		await Zotero.DB.queryAsync(sql, params, {
+			noCache: true,
+			onRow: (row, cancel) => {
+				let itemID = row.getResultByIndex(0);
+				let creatorID = row.getResultByIndex(1);
 				
-				item._creators = [];
-				item._creatorIDs = [];
-				item._loaded.creators = true;
-				item._clearChanged('creators');
-				
-				if (!row.creatorID) {
-					lastItemID = row.itemID;
-					continue;
+				if (itemID != lastItemID) {
+					if (!this._objectCache[itemID]) {
+						throw new Error("Item " + itemID + " not loaded");
+					}
+					item = this._objectCache[itemID];
+					
+					item._creators = [];
+					item._creatorIDs = [];
+					item._loaded.creators = true;
+					item._clearChanged('creators');
+					
+					if (!creatorID) {
+						lastItemID = itemID;
+						return;
+					}
+					
+					if (index <= maxOrderIndex) {
+						fixIncorrectIndexes(item, index, maxOrderIndex);
+					}
+					
+					index = 0;
+					maxOrderIndex = -1;
 				}
 				
-				if (index <= maxOrderIndex) {
-					fixIncorrectIndexes(item, index, maxOrderIndex);
+				lastItemID = itemID;
+				
+				let orderIndex = row.getResultByIndex(3);
+				if (orderIndex > maxOrderIndex) {
+					maxOrderIndex = orderIndex;
 				}
 				
-				index = 0;
-				maxOrderIndex = -1;
+				let creatorData = Zotero.Creators.get(creatorID);
+				creatorData.creatorTypeID = row.getResultByIndex(2);
+				item._creators[index] = creatorData;
+				item._creatorIDs[index] = creatorID;
+				index++;
 			}
-			
-			lastItemID = row.itemID;
-			
-			if (row.orderIndex > maxOrderIndex) {
-				maxOrderIndex = row.orderIndex;
-			}
-			
-			let creatorData = Zotero.Creators.get(row.creatorID);
-			creatorData.creatorTypeID = row.creatorTypeID;
-			item._creators[index] = creatorData;
-			item._creatorIDs[index] = row.creatorID;
-			index++;
-		}
+		});
 		
 		if (index <= maxOrderIndex) {
 			fixIncorrectIndexes(item, index, maxOrderIndex);