Version table scheme for fast version space access
AssigneeSap SE
InventorsJi Hoon Jang, Hyeong Seog Kim, Yong Sik Kwon
Life of this patent
Estimating the term…
Abstract
Methods, systems, and computer-readable storage media for determining that a first transaction results in a first version of data stored in a page in a database system, the first version being stored in a version space and the data being stored in a table space, in response to the first version, providing a version table for the page, the version table including a set of cells each cell corresponding to a record in the page, setting a version table pointer of the page to point to the version table, and setting a version pointer of a first cell to point to the first version in the version space, the first cell corresponding to a record of the data in the page.
Claims20
A computer-implemented method for providing access to a version space in database systems, the method being executed by one or more processors and comprising:
- determining that a first transaction results in a first version of data stored in a page in a database system, the first version being stored in a version space and the data being stored in a table space;
- in response to the first version, providing a version table for the page, the version table being exclusive to the page and allocated outside of the version space in heap memory, and comprising a set of cells, each cell corresponding to a record in the page and having a respective version pointer initially set to null;
- setting a version table pointer of the page to point from a respective table within the table space to the version table, the version table pointer containing a memory address of the version table within the heap memory;
- and
- setting a first version pointer of a first cell from null to point to the first version in the version space, the first cell corresponding to a record of the data in the page.
A non-transitory computer-readable storage medium coupled to one or more processors and having instructions stored thereon which, when executed by the one or more processors, cause the one or more processors to perform operations for providing access to a version space in database systems, the operations comprising:
- determining that a first transaction results in a first version of data stored in a page in a database system, the first version being stored in a version space and the data being stored in a table space;
- in response to the first version, providing a version table for the page, the version table being exclusive to the page and allocated outside of the version space in heap memory, and comprising a set of cells, each cell corresponding to a record in the page and having a respective version pointer initially set to null;
- setting a version table pointer of the page to point from a respective table within the table space to the version table, the version table pointer containing a memory address of the version table within the heap memory;
- and
- setting a first version pointer of a first cell from null to point to the first version in the version space, the first cell corresponding to a record of the data in the page.
A system, comprising:
- a computing device;
- and
- a computer-readable storage device coupled to the computing device and having instructions stored thereon which, when executed by the computing device, cause the computing device to perform operations for providing access to a version space in database systems, the operations comprising:
- determining that a first transaction results in a first version of data stored in a page in a database system, the first version being stored in a version space and the data being stored in a table space;
- in response to the first version, providing a version table for the page, the version table being exclusive to the page and allocated outside of the version space in heap memory, and comprising a set of cells, each cell corresponding to a record in the page and having a respective version pointer initially set to null;
- setting a version table pointer of the page to point from a respective table within the table space to the version table, the version table pointer containing a memory address of the version table within the heap memory;
- and
- setting a first version pointer of a first cell from null to point to the first version in the version space, the first cell corresponding to a record of the data in the page.
Dependencies are inferred from the claim text.