For ordinary compatible changes, execute supported DDL at the Publisher and let transactional replication deliver it to Subscribers. Do not independently make the same change at every Subscriber unless your replication design explicitly requires it; that can cause the replicated DDL to fail when it arrives.
Last updated: October 11, 2026.
-- Run in the publication database and confirm the current setting.
EXEC sys.sp_helppublication
@publication = N'ReportingPublication';
GO
-- With replicate_ddl enabled, run a tested compatible change
-- at the Publisher so replication preserves the operation order.
ALTER TABLE dbo.Orders
ADD SourceSystem varchar(30) NULL;
GOTest the exact vendor upgrade script against a restored copy of the publication and subscriber first. Record replication latency, verify that the Distribution Agent applies the DDL, and confirm that subsequent replicated DML succeeds before continuing the upgrade.
Know which changes propagate
Microsoft’s schema replication documentation says supported ALTER TABLE, ALTER VIEW, ALTER PROCEDURE, ALTER FUNCTION, and DML-trigger changes are propagated by default to SQL Server Subscribers. The publication property replicate_ddl controls many of these operations.
Some changes have special restrictions. Dropping or altering a replicated column affects replication metadata and may propagate even when general DDL replication is disabled. Different SQL Server versions can also disagree about data types or syntax. Review every breaking statement rather than treating the property as a universal switch.
Avoid table-designer rebuilds and improvised subscriber edits
Microsoft’s publication database guidance requires T-SQL or SMO for published tables because the SSMS designer may try to drop and recreate the object. A vendor upgrade that rebuilds tables, changes keys, or performs unsupported operations needs a planned maintenance path and may require article changes or reinitialization.
Back up the databases and script the replication topology before the window. Pause only the components required by the tested plan, preserve transaction ordering, and monitor agents afterward. Continue with safe procedure deployment, backup verification, and network-share backup permissions.
