Generating and applying redo records

One or more non-transitory storage media carrying instructions which, when executed by one or more processors, cause:

• receiving a plurality of updates that affect a multi-level index that comprises a plurality of index levels that includes at least a journal index and a main index;
• applying the plurality of updates to the main index;
• in response to determining that one or more criteria are satisfied, removing the plurality of updates from the journal index and applying the plurality of updates to the main index;
• processing a transaction that will result in one or more particular changes to data in one or more original data blocks that are part of a leaf level of the main index;
• before committing the transaction, generating and storing one or more redo records;
• wherein each redo record of the one or more redo records indicates (a) a first address of at least one data block of the one or more original data blocks, (b) at least one of the one or more particular changes, and (c) a second address of at least one data block of one or more target data blocks that reflect the at least one of the one or more particular changes.

A system comprising:

• one or more processors;
• one or more non-transitory storage media carrying instructions which, when executed by one or more processors, cause:
• receiving a plurality of updates that affect a multi-level index that comprises a plurality of index levels that includes at least a journal index and a main index;
• applying the plurality of updates to the journal index without applying the plurality of updates to the main index;
• in response to determining that one or more criteria are satisfied, removing the plurality of updates from the journal index and applying the plurality of updates to the main index;
• processing a transaction that will result in one or more particular changes to data in one or more original data blocks that are part of a leaf level of the main index;
• before committing the transaction, generating and storing one or more redo records;
• wherein each redo record of the one or more redo records indicates (a) a first address of at least one data block of the one or more original data blocks, (b) at least one of the one or more particular changes, and (c) a second address of at least one data block of one or more target data blocks that reflect the at least one of the one or more particular changes.