aliasing for accounting, where accounting real column names are the same as others, which is 0..n as opposed to previously real names and hardcoded search via those. Now we are using a look up table for the numbers mapping to look em up

web/templates/pages/add_table/builder.html

@@ -238,6 +238,7 @@
           <li><code>account_id</code> <span class="hint">system column — the account each row is posted to, written as <code>account</code></span></li>
         {% endif %}
       </ul>
+      <p class="hint">Each of these can be given a name of your own in the column list once the row is added; leave a field empty to keep the name shown here.</p>
       <p class="hint">These names are reserved: no column of your own may use them, and the table may hold only one <code>{{ page.draft.columns.pending_compound_name() }}</code>. They land where this row sits in the column list, and can be moved with it.</p>
     </div>
   {% endif %}
@@ -276,7 +277,20 @@
                 <span class="hint">&#8627;</span>
               {% endif %}
             </td>
-            <td><code>{{ row.name }}</code></td>
+            <td>
+              <code>{{ row.name }}</code>
+              {#
+                A generated column is named by the backend, so it cannot be
+                named in the request that creates the table — but the name is a
+                display name, and an alias here is applied as a rename as soon
+                as the table exists. Leaving it empty keeps the backend's name.
+              #}
+              {% if let Some(source) = row.alias_source %}
+                <input type="hidden" name="generated_alias_sources" value="{{ source }}">
+                <input name="generated_alias_names" value="{{ row.alias }}"
+                       aria-label="Alias for {{ source }}" placeholder="alias for {{ source }}">
+              {% endif %}
+            </td>
             <td>{{ row.data_type }}</td>
             <td>
               {# A compound column expands into schema-managed companions, so