Is it normal for Page_Load to trigger upon clicking a page of a GridView inside an UpdatePanel?
I have this code in my aspx page:

    <form id="form2" runat="server">
      <asp:ScriptManager ID="ItemsScriptManager" runat="server" EnablePartialRendering="true" />
      <asp:Button runat="server" ID="SearchButton" OnClick="ItemsSearch" Text="Search" />
      <asp:UpdatePanel runat="server" ID="ItemsUpdatePanel">
        <ContentTemplate>
          <asp:ObjectDataSource runat="server" ID="ItemsDS"
            TypeName="TemplateGridViewODSPagingSorting.ItemDAO" SelectMethod="GetItems" />
          <asp:GridView runat="server" ID="ItemsGridView" DataSourceID="ItemsDS"
            AllowPaging="true" AllowSorting="true" PageSize="4">
          </asp:GridView>
        </ContentTemplate>
      </asp:UpdatePanel>
    </form>

By pressing on another page of the GridView the Page_Load is triggered, is this normal behavior for a partial postback?
Is it normal for Page_Load to trigger upon clicking a page of a GridView inside an UpdatePanel?
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I have this code in my aspx page:

    <form id="form2" runat="server">
      <asp:ScriptManager ID="ItemsScriptManager" runat="server" EnablePartialRendering="true" />
      <asp:Button runat="server" ID="SearchButton" OnClick="ItemsSearch" Text="Search" />
      <asp:UpdatePanel runat="server" ID="ItemsUpdatePanel">
        <ContentTemplate>
          <asp:ObjectDataSource runat="server" ID="ItemsDS"
            TypeName="TemplateGridViewODSPagingSorting.ItemDAO" SelectMethod="GetItems" />
          <asp:GridView runat="server" ID="ItemsGridView" DataSourceID="ItemsDS"
            AllowPaging="true" AllowSorting="true" PageSize="4">
          </asp:GridView>
        </ContentTemplate>
      </asp:UpdatePanel>
    </form>

By pressing on another page of the GridView the Page_Load is triggered, is this normal behavior for a partial postback?