Help Center/ GaussDB(DWS)/ Developer Guide/ Standard data warehouse (9.1.0.x)/ GaussDB(DWS) Development Design Proposal/ GaussDB(DWS) SQL Statement Development Specifications/ UPDATE and DELETE Operations
Updated on 2024-12-18 GMT+08:00
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UPDATE and DELETE Operations

Suggestion 3.5: Preventing Simultaneous Updates or Deletions of the Same Row in a Row-store Table

Impact of rule violation:

  • Concurrent UPDATE and DELETE operations on row-store tables may cause row lock blockage and distributed deadlocks, which can lead to service errors and performance degradation.

Solution:

  • Group UPDATE and DELETE operations by primary key or distribution column. Perform parallel operations between groups while keeping operations within a group serial.

Suggestion 3.6: Avoiding Frequent or Simultaneous UPDATE and DELETE Operations on Column-store Tables

Impact of rule violation:

  • Frequent UPDATE and DELETE operations on column-store tables can result in CU bloat, leading to large space occupation and decreased access performance.
  • Concurrent UPDATE and DELETE operations on row-store tables may cause row lock blockage and distributed deadlocks, which can lead to service errors and performance degradation.

Solution:

  • Design tables with frequent UPDATE and DELETE operations as row-store tables.
  • Group UPDATE and DELETE operations by primary key or distribution column. Perform parallel operations between groups while keeping operations within a group serial.