Mysql 不同表列之间的差异

我有以下声明：

SELECT
    da.DataEstimada,
    ca.DataMoldagem,
    da.DataEnsaio,        
    da.IdadeRompimento,
    r.CompressaoConcretoId
FROM dadoscpconcreto da 
    INNER JOIN relacaodadoscpcompressaoconcreto r ON da.DadosCpConcretoId = r.DadosCpConcretoId
    INNER JOIN compressaoconcreto cc on r.CompressaoConcretoId = cc.CompressaoConcretoId
    INNER JOIN cpcaminhao ca ON da.CpCaminhaoId = ca.CpCaminhaoId
    INNER JOIN relacaoconcretocpcaminhao re ON ca.CpCaminhaoId = re.CpCaminhaoId
    INNER JOIN concreto c ON re.ConcretoId = c.ConcretoId    

WHERE r.CompressaoConcretoId = 244

这让我回想起：

数据估计|数据建模|数据集成|数据集成|数据集成|

2014-10-31 | 2014-10-24 | 2014-10-31 |空|

2014-10-31 | 2014-10-24 | 2014-10-31 |空|

2014-11-21 | 2014-10-24 | 2014-11-21 |空|

2014-11-21 | 2014-10-24 | 2014-11-21 |空|

我想创建一个函数、过程或触发器，用于区分dadoscpconcreto表的“DataEnsaio”字段和cpcaminhao表的“DataMoldagem”，并设置dadoscpconcreto表的“IdadeRompimento”字段

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我该怎么办？

我建议从阅读MySQL文档开始