Oracle DB 使用转换函数和条件表达式-Mysql Tutorial-php.cn

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Oracle DB 使用转换函数和条件表达式

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Jun 07, 2016 pm 05:32 PM

oracle

CASE表达式使你可以在SQL 语句中使用IF-THEN-ELSE逻辑，而无需调用任何过程。在简单的CASE表达式中，Oracle Server 会搜索其expr

以下代码是一个搜索CASE表达式示例。在搜索CASE表达式中，搜索从左到右进行，直到找到列出的条件，，然后它会返回相应的返回表达式。如果找不到满足的条件，但存在一个ELSE子句，则返回ELSE子句中的返回表达式，其它情况则返回NULL。

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