From caae7fd953e7d8681f07933c5f31b319aa640a4b Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@gmail.com>
Date: Fri, 6 Jul 2012 15:21:47 +0200
Subject: [PATCH] [#1536] Add documentation to the FOR UPDATE OF clause,
 indicating that DB2 may have stricter requirements regarding updatability of
 fields

---
 .../org/jooq/test/_/testcases/SelectTests.java  | 17 +++++++++++++----
 jOOQ/src/main/java/org/jooq/LockProvider.java   |  4 ++++
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/jOOQ-test/src/org/jooq/test/_/testcases/SelectTests.java b/jOOQ-test/src/org/jooq/test/_/testcases/SelectTests.java
index d96f4ea60f..26560066c1 100644
--- a/jOOQ-test/src/org/jooq/test/_/testcases/SelectTests.java
+++ b/jOOQ-test/src/org/jooq/test/_/testcases/SelectTests.java
@@ -524,16 +524,25 @@ extends BaseTest<A, AP, B, S, B2S, BS, L, X, DATE, BOOL, D, T, U, I, IPK, T658,
             case INGRES:
             case ORACLE:
             case SYBASE: {
-                Result<Record> result = create().select(TAuthor_ID())
+                Result<Record> result =
+                create().select(TAuthor_ID())
                         .from(TAuthor())
                         .forUpdate()
-                        .of(TAuthor_LAST_NAME(), TAuthor_FIRST_NAME())
+
+                        // DB2 requires a key column to be contained in the
+                        // FOR UPDATE OF ... clause
+                        .of(TAuthor_ID(),
+                            TAuthor_LAST_NAME(),
+                            TAuthor_FIRST_NAME())
                         .fetch();
                 assertEquals(2, result.size());
 
-                Result<A> result2 = create().selectFrom(TAuthor())
+                Result<A> result2 =
+                create().selectFrom(TAuthor())
                         .forUpdate()
-                        .of(TAuthor_LAST_NAME(), TAuthor_FIRST_NAME())
+                        .of(TAuthor_ID(),
+                            TAuthor_LAST_NAME(),
+                            TAuthor_FIRST_NAME())
                         .fetch();
                 assertEquals(2, result2.size());
 
diff --git a/jOOQ/src/main/java/org/jooq/LockProvider.java b/jOOQ/src/main/java/org/jooq/LockProvider.java
index a9a120d373..010d211ac0 100644
--- a/jOOQ/src/main/java/org/jooq/LockProvider.java
+++ b/jOOQ/src/main/java/org/jooq/LockProvider.java
@@ -135,6 +135,10 @@ public interface LockProvider {
      * <li>Oracle</li>
      * <li>Sybase</li>
      * </ul>
+     * <p>
+     * Note, that {@link SQLDialect#DB2} has some stricter requirements
+     * regarding the updatability of fields. Refer to the DB2 documentation for
+     * further details
      *
      * @param fields The fields that should be locked
      */