SharePoint 2010 Upgrade to 2013 ensures that users can connect but cannot modify the data being upgraded

SharePoint 2010 Upgrade to 2013 ensures that users can connect but cannot modify the data being upgraded I summarize the steps of red please pay attention to their meaning.
Step 1: Connect to the content of the SharePoint 2010 database on the SQL DBS. Step 2: Set the read-only state of the SharePoint content database to True.
Step 3: Restore the SharePoint 2010 content database backup files to the SharePoint 2013 farm.
Step 4:sharepoint The read-only state of the content database is set to False ( read-write ).
Step 5: Detach the SharePoint 2010 content database and attach it to a SharePoint 2013 environment.

translated into English. 1:connect to the SQL instance that hosts the SharePoint content database.
2:set the SharePoint content database read-only state to True.
3:back up the SharePoint content database and restore it to the SharePoint farm.
4:set the SharePoint content database read-only state to False.
5:detach the SharePoint content database and attach it in the SharePoint environment.



Backing up and restoring Databases

Steps	Notes
[ ]	Record password for Secure store Service Application The Secure Store Service application encrypts the information using a password. This password must be logged to use it in the new environment.	Complete this step once for each secure store service application in your environment.
[ ]	To set a previous version of a database to read-only If you want users to still be able to use your original environment in a read-only state, set it to read-only before backing up the database.	Complete this step for each content database in your environment. Depending on your organization, you may need a database administrator to complete this step.
[ ]	Backing Up the database Before you begin the database attach upgrade process, first back up all content databases and the following service application databases: Business Data Connectivity Managed metadata performancepoint search administration Li style= "" > Secure Store user profiles: Configuration files , social, and synchronization database	Complete this step for each content database and supported service application in your environment. This step can take an hour, a few hours, or more, depending on your data set and environment. Depending on your organization, you may need a database administrator to complete this step.
[ ]	Export the encryption key for the User profile Service application The User Profile Service application requires that the encryption key be stored separately from the database, and that the key is required when you upgrade the user Profiles synchronization database.	Complete this step once for each User profile Service application in your environment.
[ ]	Restoring a backup copy of a database Restore the database from a backup.	Complete this step for each content database and supported service application in your environment. This step may take 1 hours or more, depending on your data set and environment. Depending on your organization, you may need a database administrator to complete this step.
[ ]	To set the restored database to read-write Before you can attach and upgrade databases that are replicated to the new environment, you must first set them to read-write.	Complete this step for each content database and supported service application in your environment. Depending on your organization, you may need a database administrator to complete this step.

SharePoint 2010 Upgrade to 2013 ensures that users can connect but cannot modify data being upgraded