不需要预先确定行和列的数量。

No need to pre-determine the numbers of rows and columns.

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但随着列的数量与时俱增，这个策略可能会变得难以维护。

This strategy might become difficult to maintain as the number of columns increases over time.

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同样，键列的数量及其类型以及坐标列的类型也可能不一样。

Likewise, the number of key columns and their types will vary, as will the types of the coordinate columns.

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