Method and device for checking constraint relation of database

Abstract

The embodiment of the invention provides a constraint relation checking method and device for a database, in the constraint relation checking method, DML operation of a first transaction is executed for a target data table in the database, and each data record stored in each data table in the database has a transaction version number. And entering a submission stage, and determining a corresponding current transaction version number for the target data record after the DML operation in the submission stage. And based on the current transaction version number, reading all relevant data records which are visible and newest to the first transaction from a target data table or an associated data table thereof. Wherein the target data record and the field value, corresponding to the target field, of each related data record have a mutual restriction relationship. And based on each related data record, performing constraint relation check on a target field value, corresponding to the target field, of the target data record. And if the constraint relationship check is passed, submitting the first transaction, otherwise, rolling back.

Description

technical field [0001] One or more embodiments of this specification relate to the field of databases, and in particular, to a method and device for checking constraint relationships in a database. Background technique [0002] General relational databases provide a series of constraint definitions to limit the integrity of data in the database. In order to ensure that the constraints are not broken, after adding, deleting, and modifying operations on the database, it is usually necessary to check the constraint relationship of the data records after the adding, deleting, and modifying operations. [0003] In the traditional technology, when checking the constraint relationship, the relevant data records are usually locked. For example, for foreign key constraints, when a row of data records is added to a child table, a shared lock needs to be added to the data records corresponding to the parent table and even the entire table to prevent the parent table from being modifie...

AI Technical Summary

Problems solved by technology

For example, for foreign key constraints, when a row of data records is added to a child table, a shared lock needs to be added to the data records corresponding to the parent table and even the entire table to prevent the parent table from being modified or deleted, thereby ensuring the validity of the constraint relationship check. Locking usually causes the performance of the database to be affected

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