| CPC G06F 16/27 (2019.01) | 20 Claims |
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1. A system, comprising:
at least one processor; and
a memory, storing program instructions that when executed by the at least one processor, cause the at least one processor to implement a secondary instance of a distributed database system, wherein the secondary instance of the distributed database system provides read-only access to a database, and wherein the secondary instance is configured to:
detect one or more missing log records in an ordered replication stream of log records that describe updates to the database and are generated by a primary instance of the distributed database system that provides read-write access to the database;
for a log record received in the ordered replication stream of log records that occurs after the one or more missing log records:
identify a portion of an in-memory data structured updated by the log record and maintained in a memory at the secondary instance;
compare a sequence number recorded for the portion of the in-memory data structure that corresponds to a last update of the portion of the in-memory data structure as received at the secondary instance with a corresponding sequence number in the log record that identifies the last update corresponding to the portion of the in-memory data structure caused by the primary instance;
determine that the comparison of the sequence number recorded for the portion of the in-memory data structure and the sequence number in the log record indicate that the portion of the in-memory data structure is invalid; and
make the portion of the in-memory data structure in the memory unavailable for performing requests to the database.
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