title: Updating generator value issue
body: <p>I'm currently working on modifying a Firebird v. 1.5 database.</p>
  
  <p>The database structure will be modified running queries from a delphi application using interbase components, the problem I'm facing is that I need to run a lot of queries, some of which include creating generators and updating the generator value, the problem is that I need to achieve this in as few queries as possible, but it seems(at least to me) that this is not really possible, what I'm trying to do is the following:</p>
  
  <pre><code> /* this command creates a generator to be used for table TABLENAME */
  CREATE GENERATOR GEN_TABLENAME;
  </code></pre>
  
  <p>So I've created a generator, now I need to set it's value at the current max id from table TABLENAME, like so:</p>
  
  <pre><code>/* one would expect that the following command would work, well it doesn't */
  SET GENERATOR GEN_TABLENAME TO (SELECT MAX(ID) FROM TABLENAME);
  </code></pre>
  
  <p>Now, is there any workaround for this, or am I forced to:</p>
  
  <ul>
  <li>create the generator</li>
  <li>get the max id</li>
  <li>update the generator value</li>
  </ul>
  
  <p>and repeat process for every table?</p>
  
  <p>I also expected that</p>
  
  <pre><code>SELECT
    SELECT MAX(ID) AS ID_TABLENAME_1 FROM TABLENAME_1,
    ...
    SELECT MAX(ID) AS ID_TABLENAME_N FROM TABLENAME_N
  </code></pre>
  
  <p>would be a workaround to get the max id's from every table in one command, but it doesn't.</p>