MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE),…

MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE), another session could query the table.

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,9 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>If a FOR UPDATE query was executed twice (using a PreparedStatement), the table was not locked.
+<ul><li>MVCC: if the table was locked in exclusive mode (such as SELECT ... FOR UPDATE), another session
+    could query the table. This is now longer possible.
+</li><li>If a FOR UPDATE query was executed twice (using a PreparedStatement), the table was not locked.
 </li><li>Triggers: INSTEAD OF triggers are now supported.
     Such triggers can be defined on views.
 </li><li>MVCC: if the page store is disabled, rollback of multiple rows

h2/src/main/org/h2/table/TableData.java

@@ -425,9 +425,11 @@ public class TableData extends Table implements RecordReader {
             if (exclusive) {
                 exclusive = false;
             } else {
+                if (lockExclusive == null) {
                     return;
                 }
             }
+        }
         if (lockExclusive == session) {
             return;
         }