That comes directly from SQL. Nullable columns become Option in Rust.
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Глава МИД Ирана дал прогноз по «плану Б» Трампа20:56，推荐阅读PDF资料获取更多信息
投资建议：坚守“业绩为王、估值合理”原则，聚焦基本面稳健、估值匹配的标的；坚决规避六国化工、江钨装备、科森科技这类高偏离度、无业绩支撑的个股，警惕高位股补跌风险，合理控制仓位、理性参与市场。 （作者｜济安研究院，编辑｜蔡鹏程）
“Readers of primary source peer reviewed medical scientific journals have an absolute right to believe that the article being read is as accurate as possible, original, and factual, unless clearly specified otherwise,” said former JAMA editor George Lundberg. “‘Alternative facts,’ as popularized by Kellyanne Conway, have no place in a medical or scientific journal.”