Maximum Availability Architecture and Online Operations
60.1 Oracle MAA Tiers
Bronze: single instance + backups.
Silver: + RAC (or Data Guard).
Gold: + Active Data Guard / RAC + Data Guard.
Platinum: + GoldenGate / Application Continuity, zero downtime.
60.2 Online Operations (Minimizing Downtime)
Online index create and rebuild, online table move (12.2), online partition maintenance, online datafile move (12c), online conversion to partitioned (12.2), online SHRINK, ALTER TABLE ... ADD column DEFAULT metadata-only (11g/12c).
Online table redefinition (DBMS_REDEFINITION): Edition-Based Redefinition (EBR): upgrade PL/SQL, views, and synonyms online while old and new application versions run side by side.
Rolling patching (RAC, Data Guard), Zero Downtime Oracle Grid Infrastructure Patching, Fleet Patching.
EXEC DBMS_REDEFINITION.CAN_REDEF_TABLE('SHOP', 'ORDERS');
EXEC DBMS_REDEFINITION.START_REDEF_TABLE('SHOP', 'ORDERS', 'ORDERS_INTERIM');
-- COPY_TABLE_DEPENDENTS, SYNC_INTERIM_TABLE
EXEC DBMS_REDEFINITION.FINISH_REDEF_TABLE('SHOP', 'ORDERS', 'ORDERS_INTERIM');
-- 12.2: REDEF_TABLE single-step for simple casesALTER USER shop ENABLE EDITIONS;
CREATE EDITION release_2 AS CHILD OF ora$base;
ALTER SESSION SET EDITION = release_2;
-- modify code; editioning views + cross-edition triggers handle table changes
ALTER DATABASE DEFAULT EDITION = release_2;