This new validation will enforce NOT null column constraints by rejecting null values, but only in situations where your database would reject a null value.

这种校验会通过拒绝空值，强迫加上非空[not NULL]字段的约束，但是也只有在这种情况下，你的数据库会拒绝空值。

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If the stock is not produced, then the shorting transaction will be null and void and the broker will have to purchase the stock, says Jamie Selway, managing director at White Cap Trading.

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As a result, Botha has turned to the courts in an attempt to have his Bulls contract declared null and void, while Sarfu has not confirmed whether his Springbok contract is part of his court application.

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Translation, if one were to start with a pre-trial null hypothesis probability of 50% (reflecting equipoise, an ethical prerequisite for randomizing patients), the post-trial null hypothesis probability would still be 9%, which is not sufficient to change my practice.

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