sp_delete_firewall_rule (Azure SQL Database)
Applies to: 
Azure SQL Database
Azure Synapse Analytics
Removes server-level firewall settings from your SQL Database server. This stored procedure is only available in the master database to the server-level principal login.
Syntax
sp_delete_firewall_rule [ @name = ] N'name'
[ ; ]
Arguments
[ @name = ] N'name'
The name of the server-level firewall setting that will be removed. @name is nvarchar(128) with no default.
Remarks
In SQL Database, the credential data required to authenticate a connection and server-level firewall rules are temporarily cached in each database. This cache is periodically refreshed. To force a refresh of the authentication cache and make sure that a database has the latest version of the logins table, execute DBCC FLUSHAUTHCACHE.
Because sp_delete_firewall_rule is an extended stored procedure, the data type of the value passed in for the parameter much match exactly. Implicit conversions from other types don't take place.
Permissions
Only the server-level principal login created by the provisioning process can delete server level firewall rules. The user must be connected to the master database to execute sp_delete_firewall_rule.
Examples
The following example removes the server-level firewall setting named Example setting 1. Execute the statement in the virtual master database.
EXEC sp_delete_firewall_rule N'Example setting 1';