From 5e892a8afa63a35d86e8cb38375072e621bb3997 Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@gmail.com>
Date: Mon, 24 Sep 2018 09:29:22 +0200
Subject: [PATCH] [#7885] Add Table.rowid()

---
 jOOQ/src/main/java/org/jooq/Table.java        | 26 ++++++
 .../java/org/jooq/impl/AbstractTable.java     | 15 +++-
 jOOQ/src/main/java/org/jooq/impl/Rowid.java   | 87 +++++++++++++++++++
 3 files changed, 125 insertions(+), 3 deletions(-)
 create mode 100644 jOOQ/src/main/java/org/jooq/impl/Rowid.java

diff --git a/jOOQ/src/main/java/org/jooq/Table.java b/jOOQ/src/main/java/org/jooq/Table.java
index 7036eecf5e..1e8d1ec897 100644
--- a/jOOQ/src/main/java/org/jooq/Table.java
+++ b/jOOQ/src/main/java/org/jooq/Table.java
@@ -292,6 +292,32 @@ public interface Table<R extends Record> extends TableLike<R>, Named {
     @Support
     QualifiedAsterisk asterisk();
 
+    /**
+     * Get a <code>table.rowid</code> reference from this table.
+     * <p>
+     * A rowid value describes the physical location of a row on the disk, which
+     * can be used as a replacement for a primary key in some situations -
+     * especially within a query, e.g. to self-join a table:
+     * <p>
+     * <code><pre>
+     * -- Emulating this MySQL statement...
+     * DELETE FROM x ORDER BY x.y LIMIT 1
+     *
+     * -- ... in other databases
+     * DELETE FROM x
+     * WHERE x.rowid IN (
+     *   SELECT x.rowid FROM x ORDER BY x.a LIMIT 1
+     * )
+     * </pre></code>
+     * <p>
+     * It is <em>not</em> recommended to use <code>rowid</code> values in client
+     * applications as actual row identifiers as the database system may move a
+     * row to a different physical location at any time, thus changing the rowid
+     * value. In general, use primary keys, instead.
+     */
+    @Support({ H2, POSTGRES, SQLITE })
+    Field<?> rowid();
+
     // -------------------------------------------------------------------------
     // XXX: Aliasing clauses
     // -------------------------------------------------------------------------
diff --git a/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java b/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
index 34da0f7c6a..fdeeef1182 100644
--- a/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
+++ b/jOOQ/src/main/java/org/jooq/impl/AbstractTable.java
@@ -171,15 +171,24 @@ abstract class AbstractTable<R extends Record> extends AbstractNamed implements
         return record.into(this);
     }
 
-    // ------------------------------------------------------------------------
-    // XXX: TableLike API
-    // ------------------------------------------------------------------------
+    // -------------------------------------------------------------------------
+    // XXX: Expressions based on this table
+    // -------------------------------------------------------------------------
 
     @Override
     public final QualifiedAsterisk asterisk() {
         return new QualifiedAsteriskImpl(this);
     }
 
+    @Override
+    public final Field<?> rowid() {
+        return new Rowid(this);
+    }
+
+    // ------------------------------------------------------------------------
+    // XXX: TableLike API
+    // ------------------------------------------------------------------------
+
     /**
      * Subclasses should override this method to provide the set of fields
      * contained in the concrete table implementation. For example, a
diff --git a/jOOQ/src/main/java/org/jooq/impl/Rowid.java b/jOOQ/src/main/java/org/jooq/impl/Rowid.java
new file mode 100644
index 0000000000..05b57f96a5
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/impl/Rowid.java
@@ -0,0 +1,87 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Other licenses:
+ * -----------------------------------------------------------------------------
+ * Commercial licenses for this work are available. These replace the above
+ * ASL 2.0 and offer limited warranties, support, maintenance, and commercial
+ * database integrations.
+ *
+ * For more information, please visit: http://www.jooq.org/licenses
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+package org.jooq.impl;
+
+import static org.jooq.impl.DSL.unquotedName;
+
+import org.jooq.Context;
+import org.jooq.Table;
+
+/**
+ * @author Lukas Eder
+ */
+final class Rowid extends AbstractField<Object> {
+
+    /**
+     * Generated UID
+     */
+    private static final long serialVersionUID = 1514220224208896376L;
+    private final Table<?>    table;
+
+    Rowid(Table<?> table) {
+        super(table.getQualifiedName().append(unquotedName("rowid")), SQLDataType.OTHER);
+
+        this.table = table;
+    }
+
+    @Override
+    public final void accept(Context<?> ctx) {
+        switch (ctx.family()) {
+            case H2:
+                ctx.visit(table.getQualifiedName().append(unquotedName("_rowid_")));
+                break;
+
+            case POSTGRES:
+                ctx.visit(table.getQualifiedName().append(unquotedName("ctid")));
+                break;
+
+
+
+
+
+
+
+
+
+            case SQLITE:
+            default:
+                ctx.visit(getQualifiedName());
+                break;
+        }
+    }
+}