求一个 PostgreSQL 方法，取数组中出现频率最高的那个元素？ - V2EX
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zealinux

求一个 PostgreSQL 方法，取数组中出现频率最高的那个元素？

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  •   zealinux Nov 25, 2021 2317 views
    This topic created in 1635 days ago, the information mentioned may be changed or developed.
    比如数组：["A", "A", "B", "C"]

    结果是： "A"，如果并列则取第一个就行。
  • postgresql
  • 并列
  • 频率
  • 元素
    3 replies
    jindeq
        1
    jindeq  
       Nov 25, 2021
    没有直接的方法，你可以定义一个方法在 postgres 中。每次查询去调用。
    beginor
        3
    beginor  
       Nov 25, 2021 via Android   1
    记得 pg 有个函数可以将数组转成记录，然后再 groupby + count 就很容易了
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