All DOC_IDs are unique to meet the foreign key constraints.

所有DOC_ID都是惟一的，以满足外键约束。

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Adding or dropping unique, distinct, or foreign key constraints.

添加或删除惟一、独特或外键约束。

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Minimize the triggers, CHECK and foreign key constraints, and generated columns for the table.

尽量减少表上的触发器、检查和外键约束以及生成的列。

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"Lingering credit constraints are a key reason why I expect the strengthening in economic activity to be gradual, " says Federal Reserve Vice Chairman Donald Kohn.

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One of the key aspects of Launch KC is helping to reduce the cost constraints on launching tech companies.

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The key question is is the lower than expected number of countries due to supply constraints or higher than expected demand (or a combination of the two).

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