In-memory key-value store for a multi-model database

Patent metadata

Field	Value
Publication number	US-2017147664-A1
Application number	US-201514946489-A
Country	US
Kind code	A1
Filing date	Nov 19, 2015
Priority date	Nov 19, 2015
Publication date	May 25, 2017
Grant date	—

Abstract

Techniques related to an in-memory key-value store for a multi-model database are disclosed. In an embodiment, a relational database may be maintained on persistent storage. The relational database may be managed by a database server and may include a database table. The database table may be stored in a persistent format. Key-value records may be generated within volatile memory accessible to the database server by converting data in the database table to a key-value format. The key-value format may be different from and independent of the persistent format. A database statement referencing the database table may be executed based on determining whether to access one or more key-value records in the volatile memory or to access the data in the database table. In response to determining to access the one or more key-value records, the database server may access the one or more key-value records in the volatile memory.

First claim

What is claimed is:

1 . A method comprising:
maintaining, on persistent storage, a relational database that is managed by a database server; wherein said relational database includes a database table, said database table being stored on said persistent storage in a persistent format; generating, within volatile memory accessible to said database server, key-value records by converting data in said database table to a key-value format; wherein said key-value format is different from and independent of said persistent format; executing a database statement referencing said database table, wherein executing said database statement comprises: determining whether to access one or more key-value records in said volatile memory or to access said data in said database table; accessing one or more key-value records in said volatile memory when determining to access said one or more key-value records.

2 . The method of claim 1 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
maintaining, by said database server within said volatile memory, said key-value records transactionally consistent with said data in said database table as said database server executes database operations that make changes to said data in said database table.

3 . The method of claim 1 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
generating a key field of said key-value records, wherein said key field includes multiple fields of said database table.

4 . The method of claim 1 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
generating a value field of said key-value records, wherein said value field includes multiple fields of said database table.

5 . The method of claim 4 , wherein generating said value field of said key-value records comprises:
for each key-value record of said key-value records, storing, in said value field, respective field values of said multiple fields as a serialization of field values.

6 . The method of claim 4 , wherein generating said value field of said key-value records comprises:
indexing at least two fields of said multiple fields.

7 . The method of claim 1 , wherein determining whether to access one or more key-value records in said volatile memory or to access said data in said database table comprises:
determining whether accessing said one or more key-value records involves interpreting one or more field values.

8 . The method of claim 1 , wherein determining whether to access one or more key-value records in said volatile memory or to access said data in said database table comprises:
determining whether said one or more key-value records include indirect references to corresponding data in said database table.

9 . The method of claim 1 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
performing a join operation on said database table and another database table of said relational database.

10 . The method of claim 1 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
storing references to one or more field values of said database table.

11 . One or more non-transitory storage media storing instructions which, when processed by one or more computing devices, cause:
maintaining, on persistent storage, a relational database that is managed by a database server; wherein said relational database includes a database table, said database table being stored on said persistent storage in a persistent format; generating, within volatile memory accessible to said database server, key-value records by converting data in said database table to a key-value format; wherein said key-value format is different from and independent of said persistent format; executing a database statement referencing said database table, wherein executing said database statement comprises: determining whether to access one or more key-value records in said volatile memory or to access said data in said database table; accessing one or more key-value records in said volatile memory when determining to access said one or more key-value records.

12 . The one or more non-transitory storage media of claim 11 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
maintaining, by said database server within said volatile memory, said key-value records transactionally consistent with said data in said database table as said database server executes database operations that make changes to said data in said database table.

13 . The one or more non-transitory storage media of claim 11 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
generating a key field of said key-value records, wherein said key field includes multiple fields of said database table.

14 . The one or more non-transitory storage media of claim 11 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
generating a value field of said key-value records, wherein said value field includes multiple fields of said database table.

15 . The one or more non-transitory storage media of claim 14 , wherein generating said value field of said key-value records comprises:
for each key-value record of said key-value records, storing, in said value field, respective field values of said multiple fields as a serialization of field values.

16 . The one or more non-transitory storage media of claim 14 , wherein generating said value field of said key-value records comprises:
indexing at least two fields of said multiple fields.

17 . The one or more non-transitory storage media of claim 11 , wherein determining whether to access one or more key-value records in said volatile memory or to access said data in said database table comprises:
determining whether accessing said one or more key-value records involves interpreting one or more field values.

18 . The one or more non-transitory storage media of claim 11 , wherein determining whether to access one or more key-value records in said volatile memory or to access said data in said database table comprises:
determining whether said one or more key-value records include indirect references to corresponding data in said database table.

19 . The one or more non-transitory storage media of claim 11 , wherein generating, within said volatile memory accessible to said database server, said key-value records by converting said data in said database table to said key-value format comprises:
performing a join operation on said database table and another database table of said relational database.

Assignees

• Oracle Int Corp

Inventors

• Bussler Christoph
• Gawlick Dieter
• Gong Weiwei

Classifications

• G06F16/22

  Indexing; Data structures therefor; Storage structures · CPC title

• G06F16/258 Primary

  Data format conversion from or to a database · CPC title

• G06F17/30604

  Physics · mapped topic

• G06F17/30569 Primary

  Physics · mapped topic

• G06F17/30312

  Physics · mapped topic