From 685b7980363c9a3fd668b899257cd39291d5ade0 Mon Sep 17 00:00:00 2001
From: John Reilly <johnny_reilly@hotmail.com>
Date: Tue, 8 Oct 2024 11:33:54 +0100
Subject: [PATCH] feat: mention memoize columns mui react data grid

---
 .../index.md                                  | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/blog-website/blog/2024-10-07-static-typing-for-mui-react-data-grid-columns/index.md b/blog-website/blog/2024-10-07-static-typing-for-mui-react-data-grid-columns/index.md
index 5f2c57bc05a..980a9d7f2bb 100644
--- a/blog-website/blog/2024-10-07-static-typing-for-mui-react-data-grid-columns/index.md
+++ b/blog-website/blog/2024-10-07-static-typing-for-mui-react-data-grid-columns/index.md
@@ -158,3 +158,42 @@ export default function BasicColumnsGrid() {
 ```
 
 With this approach, you can be confident that the columns you pass to the Data Grid are correct. This is a great way to ensure that your code is correct and that you are using the Data Grid component as intended.
+
+## The importance of memoizing columns
+
+The [MUI docs say](https://mui.com/x/react-data-grid/column-definition/):
+
+> The `columns` prop should keep the same reference between two renders. The columns are designed to be definitions, to never change once the component is mounted. Otherwise, you take the risk of losing elements like column width or order. You can create the array outside the render function or memoize it.
+
+My own experience has been that I noticed no ill effects on my own use cases by **not** memoizing. When I asked the question I was advised this was still important [when you use a big number of columns and rows](https://github.com/mui/mui-x/issues/14862). To apply that to the example we've been working with, it would look like this:
+
+```tsx
+import * as React from 'react';
+import Box from '@mui/material/Box';
+import { DataGrid, GridColDef } from '@mui/x-data-grid';
+
+export default function BasicColumnsGrid() {
+  const rows = [
+    {
+      id: 1,
+      username: '@MUI',
+      age: 20,
+    },
+  ];
+
+  type ValidRow = (typeof rows)[number];
+  type ValidField = keyof ValidRow;
+  type ColumnWithValidField = { field: ValidField };
+
+  const columns = React.useMemo(() => [
+    { field: 'username', headerName: 'User' },
+    { field: 'age', headerName: 'Age' },
+  ] satisfies GridColDef<ValidRow>[] & ColumnWithValidField[], []);
+
+  return (
+    <Box sx={{ height: 250, width: '100%' }}>
+      <DataGrid columns={columns} rows={rows} />
+    </Box>
+  );
+}
+```