Json （M）Power查询是否有表的并集？

我正在学习M（powerquerylanguage）。我想使用M从restapi解析JSON。例如，可以使用。我可以看到如何使用say向下钻取一个简单的JSON字符串

let
    Source = Json.Document("{ ""glossary"": { ""title"": ""example glossary"", ""GlossDiv"": { ""title"": ""S"", ""GlossList"": { ""GlossEntry"":
        { ""ID"": ""SGML"", ""SortAs"": ""SGML"", ""GlossTerm"": ""Standard Generalized Markup Language"", ""Acronym"": ""SGML"",
          ""Abbrev"": ""ISO 8879:1986"", ""GlossDef"": { ""para"": ""A meta-markup language, used to create markup languages such as DocBook."",
          ""GlossSeeAlso"": [""GML"", ""XML""] }, ""GlossSee"": ""markup"" } } } } }"),
    glossary = Source[glossary],
    GlossDiv = glossary[GlossDiv],
    GlossList = GlossDiv[GlossList],
    GlossEntry = GlossList[GlossEntry],
    ConvertedToTable = Record.ToTable(GlossEntry)
in
    ConvertedToTable

但是，当我有一个列表，我想从中钻取一个子属性，然后像SQLUnion查询一样返回所有这些属性时，会发生什么呢。实际上，对于每种类型的查询，它更像是一个示例

因此，这里是我的非工作查询，它不进行联合，但不幸的是将第二条记录粘到了边上

let
    Source = "{""items"":["
       {""tags"":[""vba"",""permissions""],""owner"":
             {""reputation"":49,""user_id"":9073241,""user_type"":""registered"",""accept_rate"":86,""display_name"":""Kam""},
        ""is_answered"":false,""view_count"":4,""answer_count"":0,""score"":0,""question_id"":48229549},
       {""tags"":[""excel"",""vba"",""excel-vba""],""owner"":
             {""reputation"":18,""user_id"":9057704,""user_type"":""registered"",""accept_rate"":29,""display_name"":""Gregory""},
        ""is_answered"":false,""view_count"":6,""answer_count"":0,""score"":0,""question_id"":48229590}
       ]}",
    #"Parsed JSON" = Json.Document(Source),
    items = #"Parsed JSON"[items],
    item0 = items{0},
    owner0 = item0[owner],
    item1 = items{1},
    owner1 = item1[owner],
    #"Converted to Table" = Table.Combine( {Record.ToTable(owner0), Record.ToTable(owner1) })
in
    #"Converted to Table"

我真正想要的是这个输出，但不限于2条记录，而是列表中的所有记录。（上面的示例源已从此REST API中简化）

---

我想你应该先调整一下你的桌子，然后再合并它们。例如，尝试此查询

let
    Source1 = Json.Document("{""tags"":[""vba"",""permissions""],""owner"":
             {""reputation"":49,""user_id"":9073241,""user_type"":""registered"",""accept_rate"":86,""display_name"":""Kam""},
        ""is_answered"":false,""view_count"":4,""answer_count"":0,""score"":0,""question_id"":48229549}"),
    Owner1 = Table.Pivot(Record.ToTable(Source1[owner]), List.Distinct(Record.ToTable(Source1[owner])[Name]), "Name", "Value"),
    Source2 = Json.Document("{""tags"":[""excel"",""vba"",""excel-vba""],""owner"":
             {""reputation"":18,""user_id"":9057704,""user_type"":""registered"",""accept_rate"":29,""display_name"":""Gregory""},
        ""is_answered"":false,""view_count"":6,""answer_count"":0,""score"":0,""question_id"":48229590}"),
    Owner2 = Table.Pivot(Record.ToTable(Source2[owner]), List.Distinct(Record.ToTable(Source2[owner])[Name]), "Name", "Value"),
    #"Appended Query" = Table.Combine({Owner1, Owner2})
in
    #"Appended Query"

---

如果只想展开所有所有者，请尝试以下查询：

let
    Source = "{""items"":[{""tags"":[""vba"",""permissions""],""owner"":{""reputation"":49,""user_id"":9073241,""user_type"":""registered"",""accept_rate"":86,""display_name"":""Kam""},""is_answered"":false,""view_count"":4,""answer_count"":0,""score"":0,""question_id"":48229549},{""tags"":[""excel"",""vba"",""excel-vba""],""owner"":{""reputation"":18,""user_id"":9057704,""user_type"":""registered"",""accept_rate"":29,""display_name"":""Gregory""},""is_answered"":false,""view_count"":6,""answer_count"":0,""score"":0,""question_id"":48229590}]}",
    #"Parsed JSON" = Json.Document(Source),
    items = #"Parsed JSON"[items],
    #"Converted to Table" = Table.FromList(items, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
    #"Expanded Column1" = Table.ExpandRecordColumn(#"Converted to Table", "Column1", {"owner"}, {"owner"}),
    #"Expanded owner" = Table.ExpandRecordColumn(#"Expanded Column1", "owner", {"reputation", "user_id", "user_type", "display_name"}, {"reputation", "user_id", "user_type", "display_name"})
in
    #"Expanded owner"

---

是的，那是正确的格式，谢谢。现在我们可以消除每行有一个单独的变量吗？我们会使用某种形式的表达式吗？@SMeaden您甚至不需要表格。在这种情况下，组合。检查我的编辑。哇，谢谢！很抱歉，方向不对，我是powerquery的新手。你能推荐好的教程网站吗？@SMeaden不太好。我刚从谷歌上找到它，并试图帮助stackoverflow上的人们。今天之前我从未尝试过JSON解析。

let
    Source = "{""items"":[{""tags"":[""vba"",""permissions""],""owner"":{""reputation"":49,""user_id"":9073241,""user_type"":""registered"",""accept_rate"":86,""display_name"":""Kam""},""is_answered"":false,""view_count"":4,""answer_count"":0,""score"":0,""question_id"":48229549},{""tags"":[""excel"",""vba"",""excel-vba""],""owner"":{""reputation"":18,""user_id"":9057704,""user_type"":""registered"",""accept_rate"":29,""display_name"":""Gregory""},""is_answered"":false,""view_count"":6,""answer_count"":0,""score"":0,""question_id"":48229590}]}",
    #"Parsed JSON" = Json.Document(Source),
    items = #"Parsed JSON"[items],
    #"Converted to Table" = Table.FromList(items, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
    #"Expanded Column1" = Table.ExpandRecordColumn(#"Converted to Table", "Column1", {"owner"}, {"owner"}),
    #"Expanded owner" = Table.ExpandRecordColumn(#"Expanded Column1", "owner", {"reputation", "user_id", "user_type", "display_name"}, {"reputation", "user_id", "user_type", "display_name"})
in
    #"Expanded owner"