Question

我正在使用this schema，并在关键部分注意到以下内容：

df['UniqueId'] = range(0, 14571, 1)

df['StartDate'] = pd.to_datetime(df['StartDate'])
df['EndDate'] = pd.to_datetime(df['EndDate'])
#converts dates to dateTime
df2 = df.loc[df.duplicated(subset=['DeviceId'],keep=False)] 
#Returns list of trips with repeated deviceid

DeviceIds = df2['DeviceId'].tolist()
DeviceIds = list(set(DeviceIds))
df3 = pd.DataFrame(columns = ['UniqueId','Difference'])
for ID in DeviceIds: #creats mini dataframes for every DeviceId
    temp = df2.loc[df2['DeviceId'] == ID]
    temp.sort_values(by='StartDate')
    temp['PreviousEnd'] = temp['EndDate'].shift(periods=1)
    temp['Difference'] = temp['StartDate'] - temp['PreviousEnd']
    temp['Difference'] = [1 if x < pd.Timedelta('24H')
                      else 0 for x in temp['Difference']]
    temp = temp[['UniqueId','Difference']]
    df3 = pd.concat([df3,temp])
df.set_index('UniqueId').join(df3.set_index('UniqueId'),how='left')

这两个键都指的是这一部分：

    <xs:key name="KeyAnalysisType">
        <xs:selector xpath="MasterFiles/AnalysisTypeTable/AnalysisTypeTableEntry"/>
        <xs:field xpath="AnalysisType"/>
    </xs:key>
    <xs:key name="KeyAnalysisID">
        <xs:selector xpath="MasterFiles/AnalysisTypeTable/AnalysisTypeTableEntry"/>
        <xs:field xpath="AnalysisID"/>
    </xs:key>

这个双键定义是否与两个字段的复合键选择相同？ E.g。

<xs:element name="AnalysisTypeTable" minOccurs="0">
    <xs:complexType>
        <xs:sequence>
            <xs:element name="AnalysisTypeTableEntry" maxOccurs="unbounded">
                <xs:complexType>
                    <xs:sequence>
                        <xs:element name="AnalysisType" type="FAIAcodeType">
                                <xs:annotation>
                                    <xs:documentation>Analysis type identifier: e.g. CC (for Cost Center), DEP (for department), etc.</xs:documentation>
                                </xs:annotation>
                        </xs:element>
                        <xs:element name="AnalysisTypeDescription" type="FAIAlongtextType">
                                <xs:annotation>
                                    <xs:documentation>Description of the AnalysisType, e.g. "Cost Center"</xs:documentation>
                                </xs:annotation>
                        </xs:element>
                        <xs:element name="AnalysisID" type="FAIAmiddle1textType">
                                <xs:annotation>
                                    <xs:documentation>Analysis ID: e.g. 1200-HDOF-TR (for cost center treasury in the headoffice) </xs:documentation>
                                </xs:annotation>
                        </xs:element>
                        <xs:element name="AnalysisIDDescription" type="FAIAlongtextType">
                                <xs:annotation>
                                    <xs:documentation>Description of the AnalysisID: e.g. "Headoffice-Treasury".</xs:documentation>
                                </xs:annotation>
                        </xs:element>
                    </xs:sequence>
                </xs:complexType>
            </xs:element>
        </xs:sequence>
    </xs:complexType>
</xs:element>

Answer 1

双键定义在一个重要方面有所不同从复合键。拿这个示例文档：

<root>
    <item key1="A" key2="a"/>
    <item key1="B" key2="b"/>

    <reference ref1="A" ref2="a"/>
    <reference ref1="B" ref2="b"/>
</root>

让我们为key1和key2节点定义单独的密钥：

<xs:key name="Key1">
    <xs:selector xpath="item"/>
    <xs:field xpath="@key1"/>
</xs:key>
<xs:key name="Key2">
    <xs:selector xpath="item"/>
    <xs:field xpath="@key2"/>
</xs:key>

<xs:keyref name="Keyref1" refer="Key1">
    <xs:selector xpath="reference"/>
    <xs:field xpath="@ref1"/>
</xs:keyref>
<xs:keyref name="Keyref2" refer="Key2">
    <xs:selector xpath="reference"/>
    <xs:field xpath="@ref2"/>
</xs:keyref>

在这种情况下，键是分开匹配的，彼此不了解。因此，允许<reference>元素引用不同<item>个元素的键，这些元素可能是也可能不是;

<root>
    <item key1="A" key2="a"/>
    <item key1="B" key2="b"/>

    <reference ref1="A" ref2="b"/> <!-- Mix of "A" and "b" -->
    <reference ref1="B" ref2="a"/> <!-- Mix of "B" and "a" -->
</root>

另一方面，如果使用复合密钥，则使用上述文档会无效的。因为那时键被匹配为一个组，并且<reference>元素必须引用单个<item>元素匹配两个键（如第一个示例中所示）：

<xs:key name="Key12">
    <xs:selector xpath="item"/>
    <!-- Both fields belong to the same <item> element -->
    <xs:field xpath="@key1"/> 
    <xs:field xpath="@key2"/>
</xs:key>

<xs:keyref name="Keyref12" refer="Key12">
    <xs:selector xpath="reference"/>
    <!-- Both fields belong to the same <reference> element -->
    <xs:field xpath="@ref1"/>
    <xs:field xpath="@ref2"/>
</xs:keyref>

Answer 2

我不保证它在所有情况下都是绝对等效的，例如：当其中一个字段存在而另一个字段不存在时。但在正常情况下，两个字段都存在，我认为这两个结构是等价的。

两个xs：键与复合键相同？

2 个答案: