Caching DML statement context during asynchronous database system replication

A method for implementation in connection with a database system comprising:

• continuously replaying, as part of a database recovery operation, redo log records on the database system in each of a plurality of recovery queues, wherein redo log records of a table partition are placed and processed in a specific one of the plurality of recovery queues corresponding to such table partition, wherein each table partition has its own in-memory store;
• caching, during the continuous replay of redo log records and on a per table partition basis, objects that are created during replaying of the redo log records which are common across multiple database manipulation language (DML) redo log records for a same table partition, the objects comprising table level metadata information or column level metadata information;
• reusing, as part of the continuous replay of the redo log records on the secondary database system, cached objects as they are accessed during the sequential processing of DML redo records for the same table partition;
• deleting, as part of the continuous replay of the redo log records, cached objects when certain conditions associated with a database definition language (DDL) operation are met preventing such deleted cached objects from being reused, the certain conditions comprising encountering a redo log record that modifies content within a particular cached object;
• and wherein a flag is set for a DDL redo operation that spans multiple DDL redo log records for which there are interspersed DML redo log records, the flag processing the interspersed DML redo log records;
• the flag is unset when the last DDL redo log record of the DDL operation is processed.

A system comprising:

• a primary database system;
• and a secondary database system separate from the primary database system mirroring data stored in the primary database system;
• wherein the secondary database system:
• continuously replays redo log records in each of a plurality of recovery queues as part of a database recovery operation, wherein redo log records of a table partition are placed and processed in a specific one of the plurality of recovery queues corresponding to such table partition, wherein each table partition has its own in-memory store;
• caches, during the continuous replay of redo log records and on a per table partition basis, objects that are created during replaying of the redo log records which are common across multiple database manipulation language (DML) redo log records for a same table partition, the objects comprising table level metadata information or column level metadata information;
• reuses, as part of the continuous replay of the redo log records, cached objects as they are accessed during sequential processing of DML redo records for the same table partition;
• and deletes, as part of the continuous replay of the redo log records, cached objects when certain conditions associated with a database definition language (DDL) operation are met preventing such deleted cached objects from being reused, the certain conditions comprising encountering a redo log record that modifies content within a particular cached object;
• and wherein a flag is set for a DDL redo operation that spans multiple DDL redo log records for which there are interspersed DML redo log records, the flag indicating that redundant synchronization primitives are to be skipped when processing the interspersed DML redo log records;
• the flag is unset when the last DDL redo log record of the DDL operation is processed.