Systems and methods for performing incremental database backups
A computer-implemented method for performing incremental database backups may include (1) identifying a request to perform a block-level incremental backup of a database, the block-level incremental backup including data that has changed within the database since a previous block-level incremental backup of the database, (2) requesting, in response to the request, a differential backup stream from a database server of the database, (3) creating an incremental backup stream from the differential backup stream at least in part by removing at least one database block from the differential backup stream that has not changed since the previous block-level incremental backup and (4) forwarding the incremental backup stream to a backup location to create the block-level incremental backup. Various other methods, systems, and computer-readable media are also disclosed.
1. A computer-implemented method for performing incremental database backups, at least a portion of the method being performed by a computing device comprising at least one processor, the method comprising:
identifying a request to perform a block-level incremental backup of a database, the block-level incremental backup comprising data that has changed within the database during a first span of time beginning at a previous block-level incremental backup of the database and omitting data that has not changed within the database during the first span of time beginning at the previous block-level incremental backup of the database;
issuing an additional request, in response to the request, for a differential backup stream from a database server of the database, the differential backup stream comprising data that has changed within the database during an overall span of time beginning at a most recent full backup, the most recent full backup having occurred prior to the previous block-level incremental backup, and omitting data that has not changed within the database during the overall span of time beginning at the most recent full backup;
creating an incremental backup stream from the differential backup stream that comprises data that has changed during the overall span of time at least in part by removing at least one database block from the differential backup stream that has changed during the overall span of time but that has not changed during the first span of time;
forwarding the incremental backup stream to a backup location to create the block-level incremental backup.
2. The computer-implemented method of claim 1 , wherein removing the database block from the differential backup stream comprises inspecting content of the database block to determine that the database block has not changed since the previous block-level incremental backup.
3. The computer-implemented method of claim 1 , wherein removing the database block from the differential backup stream comprises inspecting a control block within the differential backup stream to determine that the database block has not changed since the previous block-level incremental backup.
4. The computer-implemented method of claim 1 , wherein removing the database block from the differential backup stream comprises:
inspecting the database block to identify a unique identifier of the database block;
inspecting the database block to identify an ordered identifier of the database block that indicates a place within a sequence at which the database block was changed;
determining that a past ordered identifier of the database block matches the ordered identifier of the database block.
5. The computer-implemented method of claim 4 , wherein determining that the past ordered identifier of the database block matches the ordered identifier of the database block comprises:
identifying a previous differential backup stream of the database;
inspecting the database block within the previous differential backup stream to identify the unique identifier of the database block and the past ordered identifier of the database block;
storing the unique identifier of the database block in association with the past ordered identifier of the database block in a log;
after identifying the database block within the differential backup stream, looking up the unique identifier of the database block in the log to retrieve the past ordered identifier.
6. The computer-implemented method of claim 1 , wherein forwarding the incremental backup stream to the backup location comprises forwarding the incremental backup stream from the database server to a backup server.
7. The computer-implemented method of claim 1 , wherein creating the incremental backup stream from the differential backup stream comprises inspecting each database block of the differential backup stream in order and determining, in order, whether to remove each database block of the differential backup stream.
8. The computer-implemented method of claim 1 , further comprising restoring the block-level incremental backup to the database.
9. A system for performing incremental database backups, the system comprising:
an identification module programmed to identify a request to perform a block-level incremental backup of a database, the block-level incremental backup comprising data that has changed within the database during a first span of time beginning at a previous block-level incremental backup of the database and omitting data that has not changed within the database during the first span of time beginning at the previous block-level incremental backup of the database;
a requesting module programmed to issue an additional request, in response to the request, for a differential backup stream from a database server of the database, the differential backup stream comprising data that has changed within the database during an overall span of time beginning at a most recent full backup, the most recent full backup having occurred prior to the previous block-level incremental backup, and omitting data that has not changed within the database during the overall span of time beginning at the most recent full backup;
a creation module programmed to create an incremental backup stream from the differential backup stream that comprises data that has changed during the overall span of time at least in part by removing at least one database block from the differential backup stream that has changed during the overall span of time but that has not changed during the first span of time;
a forwarding module programmed to forward the incremental backup stream to a backup location to create the block-level incremental backup;
at least one processor configured to execute the identification module, the requesting module, the creation module, and the forwarding module.
10. The system of claim 9 , wherein the creation module is programmed to remove the database block from the differential backup stream by inspecting content of the database block to determine that the database block has not changed since the previous block-level incremental backup.
11. The system of claim 9 , wherein the creation module is programmed to remove the database block from the differential backup stream by inspecting a control block within the differential backup stream to determine that the database block has not changed since the previous block-level incremental backup.
12. The system of claim 9 , wherein the creation module is programmed to remove the database block from the differential backup stream by:
inspecting the database block to identify a unique identifier of the database block;
inspecting the database block to identify an ordered identifier of the database block that indicates a place within a sequence at which the database block was changed;
determining that a past ordered identifier of the database block matches the ordered identifier of the database block.
13. The system of claim 12 , wherein the creation module is programmed to determine that the past ordered identifier of the database block matches the ordered identifier of the database block by:
identifying a previous differential backup stream of the database;
inspecting the database block within the previous differential backup stream to identify the unique identifier of the database block and the past ordered identifier of the database block;
storing the unique identifier of the database block in association with the past ordered identifier of the database block in a log;
after identifying the database block within the differential backup stream, looking up the unique identifier of the database block in the log to retrieve the past ordered identifier.
14. The system of claim 9 , wherein the forwarding module is programmed to forward the incremental backup stream to the backup location by forwarding the incremental backup stream from the database server to a backup server.
15. The system of claim 9 , wherein the creation module is programmed to create the incremental backup stream from the differential backup stream by inspecting each database block of the differential backup stream in order and determining, in order, whether to remove each database block of the differential backup stream.
16. The system of claim 9 , further comprising a restoring module programmed to restore the block-level incremental backup to the database.
17. A non-transitory computer-readable-storage medium comprising one or more computer-readable instructions that, when executed by at least one processor of a computing device, cause the computing device to:
identify a request to perform a block-level incremental backup of a database, the block-level incremental backup comprising data that has changed within the database during a first span of time beginning at a previous block-level incremental backup of the database and omitting data that has not changed within the database during the first span of time beginning at the previous block-level incremental backup of the database;
issuing an additional request, in response to the request, for a differential backup stream from a database server of the database, the differential backup stream comprising data that has changed within the database during an overall span of time beginning at a most recent full backup, the most recent full backup having occurred prior to the previous block-level incremental backup, and omitting data that has not changed within the database during the overall span of time beginning at the most recent full backup;
create an incremental backup stream from the differential backup stream that comprises data that has changed during the overall span of time at least in part by removing at least one database block from the differential backup stream that has changed during the overall span of time but that has not changed during the first span of time;
forward the incremental backup stream to a backup location to create the block-level incremental backup.
18. The non-transitory computer-readable-storage medium of claim 17 , wherein removing the database block from the differential backup stream comprises inspecting content of the database block to determine that the database block has not changed since the previous block-level incremental backup.
19. The non-transitory computer-readable-storage medium of claim 17 , wherein removing the database block from the differential backup stream comprises inspecting a control block within the differential backup stream to determine that the database block has not changed since the previous block-level incremental backup.
20. The non-transitory computer-readable-storage medium of claim 17 , wherein removing the database block from the differential backup stream comprises:
inspecting the database block to identify a unique identifier of the database block;
inspecting the database block to identify an ordered identifier of the database block that indicates a place within a sequence at which the database block was changed;
determining that a past ordered identifier of the database block matches the ordered identifier of the database block.