Sqlite确保输入数据的长度正确 [英] Sqlite make sure input data is correct length

问题描述

我提出问题，我得到了一个很好的答案，但带来了许多其他问题。

I asked a question to which I got a great answer but which bring many other questions.

说我创建了一个表：

 CREATE TABLE test(my_id INTEGER(2));

如何确保在INSERTING数据插入（或从csv入口）完全一个INTEGER（2），不是INTEGER（1）或任何其他动态伸展到..？
如果我不能在这里没有内存/性能问题？

How can I make sure that when INSERTING data in there (or imporing from csv atually) the field is exactly an INTEGER(2), not INTEGER(1) or anything else it would dynamically stretch to..? If I cannot are there no memory/performance issues with this?

谢谢！

推荐答案

从CSV文件导入的所有值都是字符串（但类型关联<

All values imported from CSV files are strings (but type affinity might change that).

为了确保值在一定范围内，添加一个明确的约束：

To ensure that values are in a certain range, add an explicit constraint:

CREATE TABLE test(
    my_id INTEGER CHECK (my_id BETWEEN 0 AND 100)
);

无论如何声明它们，整数值都存储在1,2,3,4， 6或8个字节，取决于值的大小。

Regardless of how they're declated, integer values are stored in 1, 2, 3, 4, 6, or 8 bytes depending only on the magnitude of the value.

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