This is a copy of the Namespacemap.xml file set up with the original namespace MyWiki, plus the added namespace SQL set as the default.

 <?xml version="1.0" encoding="utf-8"?>
 <FederationConfiguration xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <DefaultNamespace>SQL</DefaultNamespace>
  <About>If you are new to Wiki, read OneMinuteWiki or VisitorWelcome.</About>
  <WikiTalkVersion>1</WikiTalkVersion>
  <NoFollowExternalHyperlinks>0</NoFollowExternalHyperlinks>
  <DefaultDirectoryForNewNamespaces>.</DefaultDirectoryForNewNamespaces>
  <NamespaceProviders>
    <Provider Id="B75C029B-EE08-4a07-BFBD-F59E99DEA564" Type="FlexWiki.FileSystemNamespaceProvider" AssemblyName="FlexWiki, Version=1.0.10.4515, Culture=neutral, PublicKeyToken=null">
      <Parameters>
        <Parameter Name="Root" Value=".\MyWiki" />
        <Parameter Name="Namespace" Value="MyWiki" />
      </Parameters>
    </Provider>
    <Provider Id="ae97909d-e3de-4d63-9121-ecb9bec98c1a" Type="FlexWiki.SqlProvider.SqlNamespaceProvider" AssemblyName="FlexWiki.SqlProvider, Version=1.8.0.0, Culture=neutral, PublicKeyToken=null">
      <Parameters>
        <Parameter Name="Namespace" Value="SQL" />
        <Parameter Name="ConnectionString" Value="Data Source=(local);Initial Catalog=FlexwikiSqlStore;Integrated Security=true;" />
      </Parameters>
    </Provider>
  </NamespaceProviders>
  <BlacklistedExternalLinks />
  <Namespaces />
 </FederationConfiguration>