Method and system for storing shared data records in relational database

摘要

Database management system comprises a hierarchical data tree. Each tree node is assigned a unique identifier used as a primary key record in each database table. A root of the tree hierarchy is a system data field created by a service provider. None of the individual subscriptions are assigned to the system data field, but all subscribers can read data from the tree branches located under this root. The data of individual subscriptions serves as branches of a hierarchical data tree. The branches are directly connected to the root data. For each subscription, data access and update policies are set for individual database tables and for individual table records. Each database table that stores shared data has a special data field with flags. The flags define read and modify policies for each. The flags are positions within a bit mask.

主权项

1. A computer-implemented hierarchical data tree management system, the system comprising:
a computer processor; a memory coupled to the computer processor; computer code loaded into the memory for implementing the following functionality: a system data segment; a plurality of subscriber data segments organized into a hierarchical tree, with the system data segment as the root node; a shared data segment containing common subscriber data, wherein:
the system data segment is created by a service provider and write operations into the system data segment are not allowed;a copy of system data is provided on-demand to the subscriber data segments for modifications;at least partial data from the subscriber data segments is provided to the shared data segment; andwherein particular data from the system data segment becomes invisible after a first attempt of modification, and only common or subscriber data is available after copying from the system data segment; and a table storing data of different subscribers, including system data, shared data, and subscriber data, wherein the table includes a subscription id column that defines a data segment is used to determine to which data segment a database record belongs, wherein the data segments are organized in a hierarchical data tree, and the hierarchical data tree is used to walk through the table for data retrieval and data modification, such that when a record is selected, key data and subscription id are passed to the table, and then a search is performed within the subscriber data segment, in any shared data segments and in the system data segment, wherein a read flag is used to prevent returning duplicate records, wherein only one of the records with identical key data that uniquely identifies a record contains a true value in the read flag, wherein, to update a record in the table, all data segments in the hierarchy up to the root are searched by key data passed, and a write flag is analyzed, to see if an original record of the system data segment is modifiable, wherein when the original record is not modifiable, the original record is copied into either a shared data segment lower in hierarchy for the subscriber who requested the modification, or, when there is no shared data segment with write operations allowed, into the subscriber data segment, and then a modification is performed for the copy of the original record, and the read flag of the original record is updated to make it invisible for a subscriber who has a copy of the original record.