From a15c83fc25e06bba36a4e21e873605fe82e0eb7a Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@gmail.com>
Date: Wed, 26 Sep 2012 22:38:44 +0200
Subject: [PATCH] [#1844] Add Table<Record> Table.join(TableLike<?>, JoinType)
 to allow for dynamic joining

---
 .../org/jooq/test/_/testcases/JoinTests.java  | 14 ++++
 .../main/java/org/jooq/SelectJoinStep.java    | 80 ++++++++++--------
 .../java/org/jooq/SelectOptionalOnStep.java   | 82 +++++++++++++++++++
 jOOQ/src/main/java/org/jooq/Table.java        | 82 +++++++++++--------
 .../java/org/jooq/TableOptionalOnStep.java    | 48 +++++++++++
 .../java/org/jooq/impl/AbstractTable.java     | 22 +++--
 .../main/java/org/jooq/impl/JoinTable.java    |  4 +-
 .../main/java/org/jooq/impl/SelectImpl.java   | 60 ++++++++------
 8 files changed, 289 insertions(+), 103 deletions(-)
 create mode 100644 jOOQ/src/main/java/org/jooq/SelectOptionalOnStep.java
 create mode 100644 jOOQ/src/main/java/org/jooq/TableOptionalOnStep.java

diff --git a/jOOQ-test/src/org/jooq/test/_/testcases/JoinTests.java b/jOOQ-test/src/org/jooq/test/_/testcases/JoinTests.java
index 1469303533..75d107ff0e 100644
--- a/jOOQ-test/src/org/jooq/test/_/testcases/JoinTests.java
+++ b/jOOQ-test/src/org/jooq/test/_/testcases/JoinTests.java
@@ -55,6 +55,7 @@ import static org.jooq.impl.Factory.zero;
 import java.util.List;
 
 import org.jooq.Field;
+import org.jooq.JoinType;
 import org.jooq.Record;
 import org.jooq.Result;
 import org.jooq.SQLDialect;
@@ -277,6 +278,19 @@ extends BaseTest<A, AP, B, S, B2S, BS, L, X, DATE, BOOL, D, T, U, I, IPK, T658,
         assertEquals(
            asList(1, 2, 1, 2),
            result.getValues(0 + TAuthor().getFields().size(), Integer.class));
+
+        // [#1844] Cross joins can be achieved by omitting the ON clause, too
+        assertEquals(8, (int)
+        create().selectCount()
+                .from(TAuthor()
+                    .join(TBook(), JoinType.JOIN))
+                .fetchOne(0, int.class));
+
+        assertEquals(8, (int)
+        create().selectCount()
+                .from(TAuthor())
+                .join(TBook(), JoinType.CROSS_JOIN)
+                .fetchOne(0, int.class));
     }
 
     @Test
diff --git a/jOOQ/src/main/java/org/jooq/SelectJoinStep.java b/jOOQ/src/main/java/org/jooq/SelectJoinStep.java
index b0aed4530f..169968ccc7 100644
--- a/jOOQ/src/main/java/org/jooq/SelectJoinStep.java
+++ b/jOOQ/src/main/java/org/jooq/SelectJoinStep.java
@@ -61,7 +61,7 @@ import org.jooq.impl.Factory;
  * -- more than five books in German in the last three years
  * -- (from 2011), and sort those authors by last names
  * -- limiting results to the second and third row
- *
+ * 
  *   SELECT T_AUTHOR.FIRST_NAME, T_AUTHOR.LAST_NAME, COUNT(*)
  *     FROM T_AUTHOR
  *     JOIN T_BOOK ON T_AUTHOR.ID = T_BOOK.AUTHOR_ID
@@ -90,15 +90,27 @@ import org.jooq.impl.Factory;
  *       .of(TAuthor.FIRST_NAME, TAuthor.LAST_NAME)
  *       .noWait();
  * </pre></code> Refer to the manual for more details
- *
+ * 
  * @author Lukas Eder
  */
 public interface SelectJoinStep extends SelectWhereStep {
 
+    /**
+     * Convenience method to join a table to the last table added to the
+     * <code>FROM</code> clause using {@link Table#join(TableLike, JoinType)}
+     * <p>
+     * Depending on the <code>JoinType</code>, a subsequent
+     * {@link SelectOnStep#on(Condition...)} or
+     * {@link SelectOnStep#using(Field...)} clause is required. If it is
+     * required but omitted, the JOIN clause will be ignored
+     */
+    @Support
+    SelectOptionalOnStep join(TableLike<?> table, JoinType type);
+
     /**
      * Convenience method to <code>INNER JOIN</code> a table to the last table
      * added to the <code>FROM</code> clause using {@link Table#join(TableLike)}
-     *
+     * 
      * @see Table#join(TableLike)
      */
     @Support
@@ -112,7 +124,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#join(String)
      */
@@ -128,7 +140,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#join(String, Object...)
      */
@@ -144,7 +156,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#join(String, QueryPart...)
      */
@@ -162,7 +174,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * A cross join B
      * A join B on 1 = 1
      * </pre></code>
-     *
+     * 
      * @see Table#crossJoin(TableLike)
      */
     @Support
@@ -184,7 +196,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#crossJoin(String)
      */
@@ -207,7 +219,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#crossJoin(String, Object...)
      */
@@ -230,7 +242,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#crossJoin(String, QueryPart...)
      */
@@ -241,7 +253,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * Convenience method to <code>LEFT OUTER JOIN</code> a table to the last
      * table added to the <code>FROM</code> clause using
      * {@link Table#leftOuterJoin(TableLike)}
-     *
+     * 
      * @see Table#leftOuterJoin(TableLike)
      */
     @Support
@@ -256,7 +268,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#leftOuterJoin(String)
      */
@@ -272,7 +284,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#leftOuterJoin(String, Object...)
      */
@@ -288,7 +300,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#leftOuterJoin(String, QueryPart...)
      */
@@ -301,7 +313,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * {@link Table#rightOuterJoin(TableLike)}
      * <p>
      * This is only possible where the underlying RDBMS supports it
-     *
+     * 
      * @see Table#rightOuterJoin(TableLike)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -318,7 +330,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#rightOuterJoin(String)
      */
@@ -336,7 +348,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#rightOuterJoin(String, Object...)
      */
@@ -354,7 +366,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#rightOuterJoin(String, QueryPart...)
      */
@@ -367,7 +379,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * {@link Table#fullOuterJoin(TableLike)}
      * <p>
      * This is only possible where the underlying RDBMS supports it
-     *
+     * 
      * @see Table#fullOuterJoin(TableLike)
      */
     @Support({ DB2, FIREBIRD, HSQLDB, INGRES, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -384,7 +396,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#fullOuterJoin(String)
      */
@@ -402,7 +414,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#fullOuterJoin(String, Object...)
      */
@@ -420,7 +432,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#fullOuterJoin(String, QueryPart...)
      */
@@ -434,7 +446,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * <p>
      * Natural joins are supported by most RDBMS. If they aren't supported, they
      * are simulated if jOOQ has enough information.
-     *
+     * 
      * @see Table#naturalJoin(TableLike)
      */
     @Support
@@ -452,7 +464,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#naturalJoin(String)
      */
@@ -471,7 +483,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#naturalJoin(String, Object...)
      */
@@ -490,7 +502,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#naturalJoin(String, QueryPart...)
      */
@@ -504,7 +516,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * <p>
      * Natural joins are supported by most RDBMS. If they aren't supported, they
      * are simulated if jOOQ has enough information.
-     *
+     * 
      * @see Table#naturalLeftOuterJoin(TableLike)
      */
     @Support
@@ -522,7 +534,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#naturalLeftOuterJoin(String)
      */
@@ -541,7 +553,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#naturalLeftOuterJoin(String, Object...)
      */
@@ -560,7 +572,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#naturalLeftOuterJoin(String, QueryPart...)
      */
@@ -574,7 +586,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * <p>
      * Natural joins are supported by most RDBMS. If they aren't supported, they
      * are simulated if jOOQ has enough information.
-     *
+     * 
      * @see Table#naturalRightOuterJoin(TableLike)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -592,7 +604,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      * @see Table#naturalRightOuterJoin(String)
      */
@@ -611,7 +623,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      * @see Table#naturalRightOuterJoin(String, Object...)
      */
@@ -630,7 +642,7 @@ public interface SelectJoinStep extends SelectWhereStep {
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      * @see Table#naturalRightOuterJoin(String, QueryPart...)
      */
diff --git a/jOOQ/src/main/java/org/jooq/SelectOptionalOnStep.java b/jOOQ/src/main/java/org/jooq/SelectOptionalOnStep.java
new file mode 100644
index 0000000000..2edb132478
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/SelectOptionalOnStep.java
@@ -0,0 +1,82 @@
+/**
+ * Copyright (c) 2009-2012, Lukas Eder, lukas.eder@gmail.com
+ * All rights reserved.
+ *
+ * This software is licensed to you under the Apache License, Version 2.0
+ * (the "License"); You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * . Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * . Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * . Neither the name "jOOQ" nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.jooq;
+
+/**
+ * This type is used for the {@link Select}'s DSL API when selecting generic
+ * {@link Record} types.
+ * <p>
+ * Example: <code><pre>
+ * -- get all authors' first and last names, and the number
+ * -- of books they've written in German, if they have written
+ * -- more than five books in German in the last three years
+ * -- (from 2011), and sort those authors by last names
+ * -- limiting results to the second and third row
+ *
+ *   SELECT T_AUTHOR.FIRST_NAME, T_AUTHOR.LAST_NAME, COUNT(*)
+ *     FROM T_AUTHOR
+ *     JOIN T_BOOK ON T_AUTHOR.ID = T_BOOK.AUTHOR_ID
+ *    WHERE T_BOOK.LANGUAGE = 'DE'
+ *      AND T_BOOK.PUBLISHED > '2008-01-01'
+ * GROUP BY T_AUTHOR.FIRST_NAME, T_AUTHOR.LAST_NAME
+ *   HAVING COUNT(*) > 5
+ * ORDER BY T_AUTHOR.LAST_NAME ASC NULLS FIRST
+ *    LIMIT 2
+ *   OFFSET 1
+ *      FOR UPDATE
+ *       OF FIRST_NAME, LAST_NAME
+ *       NO WAIT
+ * </pre></code> Its equivalent in jOOQ <code><pre>
+ * create.select(TAuthor.FIRST_NAME, TAuthor.LAST_NAME, create.count())
+ *       .from(T_AUTHOR)
+ *       .join(T_BOOK).on(TBook.AUTHOR_ID.equal(TAuthor.ID))
+ *       .where(TBook.LANGUAGE.equal("DE"))
+ *       .and(TBook.PUBLISHED.greaterThan(parseDate('2008-01-01')))
+ *       .groupBy(TAuthor.FIRST_NAME, TAuthor.LAST_NAME)
+ *       .having(create.count().greaterThan(5))
+ *       .orderBy(TAuthor.LAST_NAME.asc().nullsFirst())
+ *       .limit(2)
+ *       .offset(1)
+ *       .forUpdate()
+ *       .of(TAuthor.FIRST_NAME, TAuthor.LAST_NAME)
+ *       .noWait();
+ * </pre></code> Refer to the manual for more details
+ *
+ * @author Lukas Eder
+ */
+public interface SelectOptionalOnStep extends SelectJoinStep, SelectJoinPartitionByStep {
+
+}
diff --git a/jOOQ/src/main/java/org/jooq/Table.java b/jOOQ/src/main/java/org/jooq/Table.java
index df605bd432..05cf243c17 100644
--- a/jOOQ/src/main/java/org/jooq/Table.java
+++ b/jOOQ/src/main/java/org/jooq/Table.java
@@ -57,7 +57,7 @@ import org.jooq.impl.Factory;
 
 /**
  * A table to be used in queries
- *
+ * 
  * @param <R> The record type associated with this table
  * @author Lukas Eder
  */
@@ -78,7 +78,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
 
     /**
      * Create an alias for this table
-     *
+     * 
      * @param alias The alias name
      * @return The table alias
      */
@@ -101,7 +101,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * <p>
      * Note: Unfortunately, this is not supported in the Oracle dialect, where
      * identities simulated by triggers cannot be formally detected.
-     *
+     * 
      * @return The table's <code>IDENTITY</code> information, or
      *         <code>null</code>, if no such information is available.
      */
@@ -109,7 +109,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
 
     /**
      * Get the list of <code>FOREIGN KEY</code>'s of this table
-     *
+     * 
      * @return This table's <code>FOREIGN KEY</code>'s. This is never
      *         <code>null</code>.
      */
@@ -118,7 +118,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
     /**
      * Get a list of <code>FOREIGN KEY</code>'s of this table, referencing a
      * specific table.
-     *
+     * 
      * @param <O> The other table's record type
      * @param other The other table of the foreign key relationship
      * @return This table's <code>FOREIGN KEY</code>'s towards an other table.
@@ -137,7 +137,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * <li>Other dialects by using some means of simulation (not yet officially
      * supported)</li>
      * </ul>
-     *
+     * 
      * @param aggregateFunctions The aggregate functions used for pivoting.
      * @return A DSL object to create the <code>PIVOT</code> expression
      */
@@ -149,7 +149,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * into another form
      * <p>
      * For more details, see {@link #pivot(Field...)}
-     *
+     * 
      * @param aggregateFunctions The aggregate functions used for pivoting.
      * @return A DSL object to create the <code>PIVOT</code> expression
      * @see #pivot(Field...)
@@ -166,7 +166,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * <code><pre>
      * Assume the following cross join / cartesian product
      * C = A × B
-     *
+     * 
      * Then it can be said that
      * A = C ÷ B
      * B = C ÷ A
@@ -199,10 +199,12 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * examples, see
      * <ul>
      * <li><a
-     * href="http://en.wikipedia.org/wiki/Relational_algebra#Division">http://en.wikipedia.org/wiki/Relational_algebra#Division</a></li>
+     * href="http://en.wikipedia.org/wiki/Relational_algebra#Division">http
+     * ://en.wikipedia.org/wiki/Relational_algebra#Division</a></li>
      * <li><a href=
      * "http://www.simple-talk.com/sql/t-sql-programming/divided-we-stand-the-sql-of-relational-division/"
-     * >http://www.simple-talk.com/sql/t-sql-programming/divided-we-stand-the-sql-of-relational-division/</a></li>
+     * >http://www.simple-talk.com/sql/t-sql-programming/divided-we-stand-the-
+     * sql-of-relational-division/</a></li>
      * </ul>
      * <p>
      * This has been observed to work with all dialects
@@ -210,6 +212,18 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
     @Support
     DivideByOnStep divideBy(Table<?> divisor);
 
+    /**
+     * Join a table to this table using a {@link JoinType}
+     * <p>
+     * Depending on the <code>JoinType</code>, a subsequent
+     * {@link TableOnStep#on(Condition...)} or
+     * {@link TableOnStep#using(Field...)} clause is required. If it is required
+     * but omitted, a {@link Factory#trueCondition()}, i.e. <code>1 = 1</code>
+     * condition will be rendered
+     */
+    @Support
+    TableOptionalOnStep join(TableLike<?> table, JoinType type);
+
     /**
      * <code>INNER JOIN</code> a table to this table.
      */
@@ -223,7 +237,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support
@@ -236,7 +250,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support
@@ -249,7 +263,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support
@@ -268,7 +282,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support
@@ -281,7 +295,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support
@@ -294,7 +308,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support
@@ -317,7 +331,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -332,7 +346,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -347,7 +361,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -370,7 +384,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support({ DB2, FIREBIRD, HSQLDB, INGRES, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -385,7 +399,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support({ DB2, FIREBIRD, HSQLDB, INGRES, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -400,7 +414,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support({ DB2, FIREBIRD, HSQLDB, INGRES, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -433,7 +447,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support
@@ -453,7 +467,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support
@@ -473,7 +487,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support
@@ -498,7 +512,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support
@@ -514,7 +528,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support
@@ -530,7 +544,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support
@@ -555,7 +569,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support
@@ -571,7 +585,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support
@@ -587,7 +601,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support
@@ -612,7 +626,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -628,7 +642,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, Object...)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
@@ -644,7 +658,7 @@ public interface Table<R extends Record> extends org.jooq.Type<R>, AliasProvider
      * guarantee syntax integrity. You may also create the possibility of
      * malicious SQL injection. Be sure to properly use bind variables and/or
      * escape literals when concatenated into SQL clauses!
-     *
+     * 
      * @see Factory#table(String, QueryPart...)
      */
     @Support({ ASE, CUBRID, DB2, DERBY, FIREBIRD, H2, HSQLDB, INGRES, MYSQL, ORACLE, POSTGRES, SQLSERVER, SYBASE })
diff --git a/jOOQ/src/main/java/org/jooq/TableOptionalOnStep.java b/jOOQ/src/main/java/org/jooq/TableOptionalOnStep.java
new file mode 100644
index 0000000000..05e80b30b4
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/TableOptionalOnStep.java
@@ -0,0 +1,48 @@
+/**
+ * Copyright (c) 2009-2012, Lukas Eder, lukas.eder@gmail.com
+ * All rights reserved.
+ *
+ * This software is licensed to you under the Apache License, Version 2.0
+ * (the "License"); You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * . Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ * . Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * . Neither the name "jOOQ" nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.jooq;
+
+/**
+ * An intermediate type for the construction of a <code>JOIN</code> clause,
+ * where there may optionally be a join criteria added using an <code>ON</code>
+ * clause (with a {@link Condition}), or using a <code>USING</code> clause (with
+ * a list of {@link Field})
+ *
+ * @author Lukas Eder
+ */
+public interface TableOptionalOnStep extends TablePartitionByStep, Table<Record> {
+
+}
diff --git a/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java b/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
index 6c188a71b1..eafc5ac5b4 100644
--- a/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
+++ b/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
@@ -56,6 +56,7 @@ import org.jooq.Table;
 import org.jooq.TableField;
 import org.jooq.TableLike;
 import org.jooq.TableOnStep;
+import org.jooq.TableOptionalOnStep;
 import org.jooq.TablePartitionByStep;
 
 abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQueryPart<R> implements Table<R> {
@@ -185,9 +186,14 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
     // XXX: JOIN API
     // ------------------------------------------------------------------------
 
+    @Override
+    public TableOptionalOnStep join(TableLike<?> table, JoinType type) {
+        return new JoinTable(this, table, type);
+    }
+
     @Override
     public final TableOnStep join(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.JOIN);
+        return join(table, JoinType.JOIN);
     }
 
     @Override
@@ -207,7 +213,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final TablePartitionByStep leftOuterJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.LEFT_OUTER_JOIN);
+        return join(table, JoinType.LEFT_OUTER_JOIN);
     }
 
     @Override
@@ -227,7 +233,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final TablePartitionByStep rightOuterJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.RIGHT_OUTER_JOIN);
+        return join(table, JoinType.RIGHT_OUTER_JOIN);
     }
 
     @Override
@@ -247,7 +253,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final TableOnStep fullOuterJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.FULL_OUTER_JOIN);
+        return join(table, JoinType.FULL_OUTER_JOIN);
     }
 
     @Override
@@ -267,7 +273,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final Table<Record> crossJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.CROSS_JOIN);
+        return join(table, JoinType.CROSS_JOIN);
     }
 
     @Override
@@ -287,7 +293,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final Table<Record> naturalJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.NATURAL_JOIN);
+        return join(table, JoinType.NATURAL_JOIN);
     }
 
     @Override
@@ -307,7 +313,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final Table<Record> naturalLeftOuterJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.NATURAL_LEFT_OUTER_JOIN);
+        return join(table, JoinType.NATURAL_LEFT_OUTER_JOIN);
     }
 
     @Override
@@ -327,7 +333,7 @@ abstract class AbstractTable<R extends Record> extends AbstractFieldProviderQuer
 
     @Override
     public final Table<Record> naturalRightOuterJoin(TableLike<?> table) {
-        return new JoinTable(this, table, JoinType.NATURAL_RIGHT_OUTER_JOIN);
+        return join(table, JoinType.NATURAL_RIGHT_OUTER_JOIN);
     }
 
     @Override
diff --git a/jOOQ/src/main/java/org/jooq/impl/JoinTable.java b/jOOQ/src/main/java/org/jooq/impl/JoinTable.java
index 05f8818a44..dad357291f 100644
--- a/jOOQ/src/main/java/org/jooq/impl/JoinTable.java
+++ b/jOOQ/src/main/java/org/jooq/impl/JoinTable.java
@@ -73,7 +73,7 @@ import org.jooq.TableField;
 import org.jooq.TableLike;
 import org.jooq.TableOnConditionStep;
 import org.jooq.TableOnStep;
-import org.jooq.TablePartitionByStep;
+import org.jooq.TableOptionalOnStep;
 import org.jooq.exception.DataAccessException;
 
 /**
@@ -81,7 +81,7 @@ import org.jooq.exception.DataAccessException;
  *
  * @author Lukas Eder
  */
-class JoinTable extends AbstractTable<Record> implements TableOnConditionStep, TablePartitionByStep {
+class JoinTable extends AbstractTable<Record> implements TableOptionalOnStep, TableOnConditionStep {
 
     /**
      * Generated UID
diff --git a/jOOQ/src/main/java/org/jooq/impl/SelectImpl.java b/jOOQ/src/main/java/org/jooq/impl/SelectImpl.java
index dac1fe2c65..e374f98bff 100644
--- a/jOOQ/src/main/java/org/jooq/impl/SelectImpl.java
+++ b/jOOQ/src/main/java/org/jooq/impl/SelectImpl.java
@@ -57,11 +57,11 @@ import org.jooq.SelectConditionStep;
 import org.jooq.SelectConnectByConditionStep;
 import org.jooq.SelectForUpdateOfStep;
 import org.jooq.SelectHavingConditionStep;
-import org.jooq.SelectJoinPartitionByStep;
 import org.jooq.SelectJoinStep;
 import org.jooq.SelectOffsetStep;
 import org.jooq.SelectOnConditionStep;
 import org.jooq.SelectOnStep;
+import org.jooq.SelectOptionalOnStep;
 import org.jooq.SelectQuery;
 import org.jooq.SelectSelectStep;
 import org.jooq.SortField;
@@ -79,7 +79,7 @@ class SelectImpl extends AbstractDelegatingSelect<Record> implements
 
     // Cascading interface implementations for Select behaviour
     SelectSelectStep,
-    SelectJoinPartitionByStep,
+    SelectOptionalOnStep,
     SelectOnConditionStep,
     SelectConditionStep,
     SelectConnectByConditionStep,
@@ -689,59 +689,69 @@ class SelectImpl extends AbstractDelegatingSelect<Record> implements
 
     @Override
     public final SelectImpl join(TableLike<?> table) {
-        return join0(table, JoinType.JOIN);
+        return join(table, JoinType.JOIN);
     }
 
     @Override
     public final SelectImpl leftOuterJoin(TableLike<?> table) {
-        return join0(table, JoinType.LEFT_OUTER_JOIN);
+        return join(table, JoinType.LEFT_OUTER_JOIN);
     }
 
     @Override
     public final SelectImpl rightOuterJoin(TableLike<?> table) {
-        return join0(table, JoinType.RIGHT_OUTER_JOIN);
+        return join(table, JoinType.RIGHT_OUTER_JOIN);
     }
 
     @Override
     public final SelectOnStep fullOuterJoin(TableLike<?> table) {
-        return join0(table, JoinType.FULL_OUTER_JOIN);
+        return join(table, JoinType.FULL_OUTER_JOIN);
     }
 
-    private final SelectImpl join0(TableLike<?> table, JoinType type) {
-        conditionStep = ConditionStep.ON;
-        joinTable = table;
-        joinType = type;
-        joinPartitionBy = null;
-        joinConditions = null;
-        return this;
+    @Override
+    public final SelectImpl join(TableLike<?> table, JoinType type) {
+        switch (type) {
+            case CROSS_JOIN:
+            case NATURAL_JOIN:
+            case NATURAL_LEFT_OUTER_JOIN:
+            case NATURAL_RIGHT_OUTER_JOIN: {
+                getQuery().addJoin(table, type);
+                joinTable = null;
+                joinPartitionBy = null;
+                joinType = null;
+
+                return this;
+            }
+
+            default: {
+                conditionStep = ConditionStep.ON;
+                joinTable = table;
+                joinType = type;
+                joinPartitionBy = null;
+                joinConditions = null;
+
+                return this;
+            }
+        }
     }
 
     @Override
     public final SelectJoinStep crossJoin(TableLike<?> table) {
-        return simpleJoin0(table, JoinType.CROSS_JOIN);
+        return join(table, JoinType.CROSS_JOIN);
     }
 
     @Override
     public final SelectImpl naturalJoin(TableLike<?> table) {
-        return simpleJoin0(table, JoinType.NATURAL_JOIN);
+        return join(table, JoinType.NATURAL_JOIN);
     }
 
     @Override
     public final SelectImpl naturalLeftOuterJoin(TableLike<?> table) {
-        return simpleJoin0(table, JoinType.NATURAL_LEFT_OUTER_JOIN);
+        return join(table, JoinType.NATURAL_LEFT_OUTER_JOIN);
     }
 
     @Override
     public final SelectImpl naturalRightOuterJoin(TableLike<?> table) {
-        return simpleJoin0(table, JoinType.NATURAL_RIGHT_OUTER_JOIN);
-    }
-
-    private final SelectImpl simpleJoin0(TableLike<?> table, JoinType type) {
-        getQuery().addJoin(table, type);
-        joinTable = null;
-        joinPartitionBy = null;
-        joinType = null;
-        return this;
+        return join(table, JoinType.NATURAL_RIGHT_OUTER_JOIN);
     }
 
     @Override