In SQL Server Management Studio, by default you can only Select Top 1000 Rows or Edit Top 200 Rows for a table as shown in the below snippet.
The default option as shown above is to Select Top 100 Rows or Edit Top 200 Rows. This can be changed by following these steps.
1. In SQL Server Management Studio, under Tools, click Options as shown in the snippet below.
2. In the Options dialog box, expand SQL Server Object Explorer and then select the Commands tab as shown in the snippet below. Change the Value for Edit Top Rows command and/or Value for Select Top Rows command to a suitable value as per your needs as shown in the below snippet and then click OK.
3. Once you have saved the changes go ahead and right click on a table to see the changes as shown below.