将 mysql 查询转换为 MS SQL

Question

您好我想知道是否有人可以帮助我，我有以下 MySQL 查询（摘录）：

concat_ws('\n', 
                    IF(LENGTH(PafAddress.line1),PafAddress.line1,NULL),
                    IF(LENGTH(PafAddress.line2),PafAddress.line2,NULL),
                    IF(LENGTH(PafAddress.line3),PafAddress.line3,NULL),
                    IF(LENGTH(PafAddress.line4),PafAddress.line4,NULL),
                    IF(LENGTH(PafAddress.Line5),PafAddress.line5,NULL),
                    IF(LENGTH(PafAddress.post_town),PafAddress.post_town,NULL),
                    IF(LENGTH(PafAddress.county),PafAddress.county,NULL),
                    IF(LENGTH(PafAddress.postcode),PafAddress.postcode,NULL)
) AS AddressLabel

它从另一个表中获取多个地址字段并将其放入 memofield 格式，带有换行符，并删除空地址行。

在 MySQL 中完美运行。

我现在正试图在一个由 MS Access 运行的 PHP 网站上实现它（不是我的选择！），它不喜欢这种语法。

我不是 MS Access 专家，如果有人告诉我如何在 Access SQL 中实现这一点，我将不胜感激。

Answer 1

尝试使用 IIF(condition, truevalue, falsevalue) 语句。此外，您可以使用 &

连接

这里有两个参考资料供您参考： article about using IIF 和 article about concatenating using & 和 article about len() instead of length()

所以你的代码可能看起来像这样：

IIF(Len(PafAddress.line1)>0,PafAddress.line1,"") & " " &
IIF(Len(PafAddress.line2)>0,PafAddress.line2,"") & " " &
IIF(Len(PafAddress.line3)>0,PafAddress.line3,"") & " " &
IIF(Len(PafAddress.line4)>0,PafAddress.line4,"") & " " &
IIF(Len(PafAddress.Line5)>0,PafAddress.line5,"") & " " &
IIF(Len(PafAddress.post_town)>0,PafAddress.post_town,"") & " " &
IIF(Len(PafAddress.county)>0,PafAddress.county,"") & " " &
IIF(Len(PafAddress.postcode)>0,PafAddress.postcode,"") 
AS AddressLabel

要跳过空记录，请尝试使用：

iif( Len(PafAddress.line1)>0 
     OR Len(PafAddress.line2)>0
     OR Len(PafAddress.line3)>0
     OR Len(PafAddress.line4)>0
     OR Len(PafAddress.line5)>0
     OR Len(PafAddress.post_town)>0
     OR Len(PafAddress.county)>0
     OR Len(PafAddress.postcode)>0 
,
IIF(Len(PafAddress.line1)>0,PafAddress.line1,"") & " " &
IIF(Len(PafAddress.line2)>0,PafAddress.line2,"") & " " &
IIF(Len(PafAddress.line3)>0,PafAddress.line3,"") & " " &
IIF(Len(PafAddress.line4)>0,PafAddress.line4,"") & " " &
IIF(Len(PafAddress.Line5)>0,PafAddress.line5,"") & " " &
IIF(Len(PafAddress.post_town)>0,PafAddress.post_town,"") & " " &
IIF(Len(PafAddress.county)>0,PafAddress.county,"") & " " &
IIF(Len(PafAddress.postcode)>0,PafAddress.postcode,"" & char(13) & char(10) )
,"") 
AS AddressLabel

在这个查询中，(1st) 检查任何值的长度是否大于 0...如果是，则输出带有 CRLF 的地址行；否则输出一个空字符串。