Supporting Workbook Cache (Cell B2)

The corresponding content from externalLink1.xml is:

<externalLink …>
  <externalBook xmlns:r="http://…/relationships" r:id="rId1">
    <sheetNames>
      <sheetName val="Sheet1"/>
      <sheetName val="Sheet2"/>
      <sheetName val="Sheet3"/>
    </sheetNames>
    <sheetDataSet>
      <sheetData sheetId="0">
        <row r="1">
          <cell r="A1">
            <v>1</v>
          </cell>
        </row>
        <row r="2">
          <cell r="A2">
            <v>2</v>
          </cell>
        </row>
        <row r="3">
          <cell r="A3">
            <v>3</v>
          </cell>
        </row>
      </sheetData>
      <sheetData sheetId="1"/>
      <sheetData sheetId="2"/>
    </sheetDataSet>
  </externalBook>
</externalLink>

This supporting workbook data cache indicates that the workbook being referenced by B2 has three sheets, whose names are "Sheet1", "Sheet2", and "Sheet3". Additionally, the cell table shows that cells A1, A2, and A3, whose values are 1, 2, and 3, respectively, in this workbook are being referenced. A copy of the cell table is stored locally, inside the workbook containing the external link.

The @r:id="rId1" on the top level <externalLink> element indicates the @Id of the relationship from the externalLink1.xml part, which indicates the location of the actual external workbook.