[Tweaks
John Goerzen <jgoerzen@complete.org>**20071114082208] {
hunk ./en/ch21-databases.xml 493
+      <para>
+        Please note that some databases may not be able to provide all
+        this metadata.  In these circumstances, an exception will be
+        raised.
+      </para>
hunk ./en/ch21-databases.xml 540
+        <remark>FIXME: insert ref to data.typeable, app c</remark>
hunk ./en/ch21-databases.xml 544
-    <sect1 id="hs.databases.typeable">
-      <title>Data.Typeable</title>
-      <para><remark>FIXME</remark></para>
-    </sect1>
-
hunk ./en/ch21-databases.xml 546
-      <para><remark>FIXME</remark></para>
+      <para>
+        Different database systems have different capabilities
+        regarding multithreading.  The HDBC API spec suggests that, to
+        be safe, you should not try to issue more than one
+        simultaneous query over a single connection.  Though you may
+        use a single connection serially across multiple threads.
+      </para>
}