Question

我在Tableau中运行了if语句（如下所示）。我需要把它变成SQl - 我已经尝试了很多不同的case语句，但它们都会出错。

有人可以建议我这样做吗？

    IF LEN(REPLACE([postcode]," ","")) = 7 THEN LEFT(REPLACE([postcode]," ",""),4)+" "+RIGHT(REPLACE([postcode]," ",""),3)
ELSEIF LEN(REPLACE([postcode]," ","")) = 6 THEN LEFT(REPLACE([postcode]," ",""),3)+" "+RIGHT(REPLACE([postcode]," ",""),3)
ELSEIF LEN(REPLACE([postcode]," ","")) = 5 THEN LEFT(REPLACE([postcode]," ",""),2)+" "+RIGHT(REPLACE([postcode]," ",""),3)
END

Answer 1

尝试使用它：

SELECT
  CASE
    WHEN LEN(REPLACE([postcode],' ','')) = 7
    THEN LEFT(REPLACE([postcode],' ',''),4)+' '+RIGHT(REPLACE([postcode],' ',''),3)
    WHEN LEN(REPLACE([postcode],' ','')) = 6
    THEN LEFT(REPLACE([postcode],' ',''),3)+' '+RIGHT(REPLACE([postcode],' ',''),3)
    WHEN LEN(REPLACE([postcode],' ','')) = 5
    THEN LEFT(REPLACE([postcode],' ',''),2)+' '+RIGHT(REPLACE([postcode],' ',''),3)
    ELSE 'ERROR'
  END
FROM YOUR_TABLE

Answer 2

您可以通过IF替换语句中的CASE WHEN 以及ELSEIF

所有WHEN

但您可以将其简化为：

CASE 
WHEN LEN(REPLACE([POSTCODE]," ","")) IN (5,6,7) THEN REPLACE ([POSTCODE]," ","")
ELSE NULL
END

自f.e。 “ABC”+“DEF”=“ABCDEF”=“ABC DEF”没有空格。

Answer 3

正如OP在一些查询后所说的那样，他在Hadoop上使用Hive - 而不是普通的SQL。

所以 - 也许 - 这可以让你开始：https://de.hortonworks.com/blog/hive-cheat-sheet-for-sql-users/

如果SQL中的语句怎么做呢

3 个答案: