In an HA cluster, some of the changes to a primary server’s database must be forwarded to the companion server to keep both servers synchronized.
Several DDL commands, when executed within a database that has a system proxy database, cause notification of the companion server and result in automatic synchronization of the resulting changes:
create table and drop table – local operation executes, resulting in the local table being created or dropped. The command is then forwarded to the companion server, for execution in the system proxy database, so that a proxy table can be created or dropped
create index and drop index – local operation executes, resulting in an index being created or dropped. The server owning the system proxy database is then notified, and the proxy table is dropped and re-created, allowing the change to the index to be represented within the proxy table.
create view and drop view – the local operation succeeds, resulting in the local view being created or dropped. The server owning the system proxy database is then notified, and a proxy table is either created or dropped.
If these commands are executed within the system proxy database, similar behavior occurs:
create table and drop table – local proxy table is created or dropped. The command is then forwarded to the primary server, so that a local table referenced by the proxy table can be created or dropped.
create index and drop index – local operation on the proxy table executes, resulting in an index being created or dropped. The server owning the primary database is then notified, and an index is either created or dropped on the local table referenced by the proxy table
create view and drop view – not allowed within a system proxy database.
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