# 13. 一致性管理（Concurrency Control）

本章描述兩個或更多連線在同一時間嘗試存取相同資料時 PostgreSQL 資料庫系統的行為。這種情況下的目標是讓所有的連線都能進行高效率的存取，同時保持嚴格的資料一致性。每個資料庫應用程式開發人員都應該熟悉本章所涉及的主題。


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