diff --git a/empire-db/src/main/java/org/apache/empire/db/DBCommand.java b/empire-db/src/main/java/org/apache/empire/db/DBCommand.java
index 7899c57..6a31fbd 100644
--- a/empire-db/src/main/java/org/apache/empire/db/DBCommand.java
+++ b/empire-db/src/main/java/org/apache/empire/db/DBCommand.java
@@ -1480,7 +1480,7 @@
      * 
      * @return an update SQL-Statement
      */
-    public String getUpdate()
+    public final String getUpdate()
     {
         resetParamUsage();
         if (set == null)
@@ -1489,30 +1489,40 @@
         DBRowSet table =  set.get(0).getTable();
         if (joins!=null && !joins.isEmpty())
         {   // Join Update
-            buf.append( table.getAlias() );
-            long context = CTX_DEFAULT;
-            // Set Expressions
-            buf.append("\r\nSET ");
-            addListExpr(buf, set, context, ", ");
-            // From clause
-            addFrom(buf);
-            // Add Where
-            addWhere(buf, context);
+            addUpdateWithJoins(buf, table);
         }
         else
         {   // Simple Statement
-            table.addSQL(buf, CTX_FULLNAME);
-            long context = CTX_NAME | CTX_VALUE;
-            // Set Expressions
-            buf.append("\r\nSET ");
-            addListExpr(buf, set, context, ", ");
-            // Add Where
-            addWhere(buf, context);
+            addUpdateForTable(buf, table);
         }
         // done
         completeParamUsage();
         return buf.toString();
     }
+
+    protected void addUpdateForTable(StringBuilder buf, DBRowSet table)
+    {   // Simple Statement
+        table.addSQL(buf, CTX_FULLNAME);
+        long context = CTX_NAME | CTX_VALUE;
+        // Set Expressions
+        buf.append("\r\nSET ");
+        addListExpr(buf, set, context, ", ");
+        // Add Where
+        addWhere(buf, context);
+    }
+    
+    protected void addUpdateWithJoins(StringBuilder buf, DBRowSet table)
+    {   // Join Update
+        buf.append( table.getAlias() );
+        long context = CTX_DEFAULT;
+        // Set Expressions
+        buf.append("\r\nSET ");
+        addListExpr(buf, set, context, ", ");
+        // From clause
+        addFrom(buf);
+        // Add Where
+        addWhere(buf, context);
+    }
     
     /**
      * Creates a delete SQL-Statement
@@ -1521,30 +1531,40 @@
      * 
      * @return a delete SQL-Statement
      */
-    public String getDelete(DBTable table)
+    public final String getDelete(DBTable table)
     {
         resetParamUsage();
         StringBuilder buf = new StringBuilder("DELETE ");
         // joins or simple
         if (joins!=null && !joins.isEmpty())
         {   // delete with joins
-            table.addSQL(buf, CTX_FULLNAME);
-            // From clause
-            addFrom(buf);
-            // Add Where
-            addWhere(buf, CTX_DEFAULT);
+            addDeleteWithJoins(buf, table);
         }
         else
         {   // Simple Statement
-            buf.append("FROM ");
-            table.addSQL(buf, CTX_FULLNAME);
-            // where
-            addWhere(buf, CTX_NAME|CTX_VALUE);
+            addDeleteForTable(buf, table);
         }
         // done
         completeParamUsage();
         return buf.toString();
     }
+
+    protected void addDeleteForTable(StringBuilder buf, DBRowSet table)
+    {   // Simple Statement
+        buf.append("FROM ");
+        table.addSQL(buf, CTX_FULLNAME);
+        // where
+        addWhere(buf, CTX_NAME|CTX_VALUE);
+    }
+    
+    protected void addDeleteWithJoins(StringBuilder buf, DBRowSet table)
+    {   // delete with joins
+        table.addSQL(buf, CTX_FULLNAME);
+        // From clause
+        addFrom(buf);
+        // Add Where
+        addWhere(buf, CTX_DEFAULT);
+    }
     
     // ------- Select Statement Parts -------
 
diff --git a/empire-db/src/main/java/org/apache/empire/db/DBRowSet.java b/empire-db/src/main/java/org/apache/empire/db/DBRowSet.java
index 2d96411..88359d7 100644
--- a/empire-db/src/main/java/org/apache/empire/db/DBRowSet.java
+++ b/empire-db/src/main/java/org/apache/empire/db/DBRowSet.java
@@ -302,6 +302,9 @@
 
     public abstract void deleteRecord(Object[] key, DBContext context);
     
+    @Override
+    public abstract DBColumn[] getKeyColumns();
+    
     /**
      * Returns the full qualified name of the rowset.
      * <P>
@@ -621,7 +624,7 @@
         // Init Key Values
         if (key != null)
         {   // Check Columns
-            DBColumn[] keyColumns =(DBColumn[])getKeyColumns();
+            DBColumn[] keyColumns = getKeyColumns();
             if (keyColumns==null)
                 throw new NoPrimaryKeyException(this);
             if (key.length!=keyColumns.length)
@@ -667,7 +670,7 @@
         prepareInitRecord(record, false);
         // Get Record Field Values
         Object[] fields = record.getFields();
-        DBColumn[] keyColumns =(DBColumn[])getKeyColumns();
+        DBColumn[] keyColumns = getKeyColumns();
         for (int i = 0; i < fields.length; i++)
         {   // Read a value
         	DBColumnExpr column = getColumnExprAt(i);
@@ -757,7 +760,7 @@
     protected DBCompareExpr getKeyConstraints(Object[] key)
     {
         // Check Primary key
-        DBColumn[] keyColumns =(DBColumn[])getKeyColumns();
+        DBColumn[] keyColumns = getKeyColumns();
         if (keyColumns==null || keyColumns.length==0) 
             throw new NoPrimaryKeyException(this); // Invalid Argument
         // Check Columns
@@ -966,7 +969,7 @@
         String sql = null;
         int setCount = 0;
         // Perform action
-        DBColumn[] keyColumns =(DBColumn[])getKeyColumns();
+        DBColumn[] keyColumns = getKeyColumns();
         DBRecordBase.State recordState = record.getState(); 
         if (recordState==DBRecordBase.State.New)
         {	// Insert Record
@@ -1124,7 +1127,7 @@
     {
         // Merge Sub-Records
         List<DBRelation> relations = db.getRelations();
-        DBColumn[] keyColumns =(DBColumn[])getKeyColumns();
+        DBColumn[] keyColumns = getKeyColumns();
         if (keyColumns==null)
             return; // No primary key - no references!
         // Find all relations
@@ -1158,7 +1161,7 @@
         if (refs.length!=parentKey.length)
             throw new InvalidArgumentException("refs", refs);
         // Rowset
-        DBColumn[] keyColumns =(DBColumn[])getKeyColumns();
+        DBColumn[] keyColumns = getKeyColumns();
         if (keyColumns==null || keyColumns.length==0)
         {   // No Primary Key
             DBCommand cmd = createRecordCommand(context);
diff --git a/empire-db/src/main/java/org/apache/empire/dbms/hsql/DBCommandHSql.java b/empire-db/src/main/java/org/apache/empire/dbms/hsql/DBCommandHSql.java
index 97cace1..bc88c43 100644
--- a/empire-db/src/main/java/org/apache/empire/dbms/hsql/DBCommandHSql.java
+++ b/empire-db/src/main/java/org/apache/empire/dbms/hsql/DBCommandHSql.java
@@ -19,7 +19,6 @@
 package org.apache.empire.dbms.hsql;
 
 import java.util.ArrayList;
-// Imports
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
@@ -95,27 +94,13 @@
             }    
         }
     }
-    
-    /**
-     * Creates an update statement.
-     * If a join is required, this method creates a "MERGE INTO" expression 
-     */
+
     @Override
-    public synchronized String getUpdate()
-    {
-        // No Joins: Use Default
-        if (joins==null || set==null)
-            return super.getUpdate();
-        else
-            return getUpdateWithJoins();
-    }
-    
-    protected String getUpdateWithJoins()
+    protected void addUpdateWithJoins(StringBuilder buf, DBRowSet table)
     {
         // Generate Merge expression
-        resetParamUsage();
-        StringBuilder buf = new StringBuilder("MERGE INTO ");
-        DBRowSet table =  set.get(0).getTable();
+        buf.setLength(0);
+        buf.append("MERGE INTO ");
         table.addSQL(buf, CTX_FULLNAME|CTX_ALIAS);
         // join (only one allowed yet)
         DBColumnJoinExpr updateJoin = null;
@@ -217,8 +202,6 @@
         buf.append(")\r\nWHEN MATCHED THEN UPDATE ");
         buf.append("\r\nSET ");
         addListExpr(buf, mergeSet, CTX_DEFAULT, ", ");
-        // done
-        return buf.toString();
     }
         
     protected boolean isSetColumn(DBColumn col)
diff --git a/empire-db/src/main/java/org/apache/empire/dbms/mysql/DBMSHandlerMySQL.java b/empire-db/src/main/java/org/apache/empire/dbms/mysql/DBMSHandlerMySQL.java
index d613fce..81bedd6 100644
--- a/empire-db/src/main/java/org/apache/empire/dbms/mysql/DBMSHandlerMySQL.java
+++ b/empire-db/src/main/java/org/apache/empire/dbms/mysql/DBMSHandlerMySQL.java
@@ -32,6 +32,7 @@
 import org.apache.empire.db.DBDDLGenerator.DDLActionType;
 import org.apache.empire.db.DBDatabase;
 import org.apache.empire.db.DBObject;
+import org.apache.empire.db.DBRowSet;
 import org.apache.empire.db.DBSQLScript;
 import org.apache.empire.db.DBTable;
 import org.apache.empire.db.DBTableColumn;
@@ -112,21 +113,13 @@
          * @return the delete SQL-Command
          */
         @Override
-        public synchronized String getDelete(DBTable table)
+        protected void addDeleteWithJoins(StringBuilder buf, DBRowSet table)
         {
-        	if (joins == null) {
-        		// Default
-        		return super.getDelete(table);
-        	}
-        	
-        	// DELETE with Multiple-Table Syntax
-        	// http://dev.mysql.com/doc/refman/5.7/en/delete.html
-            resetParamUsage();
-            StringBuilder buf = new StringBuilder("DELETE ");
+            // DELETE with Multiple-Table Syntax
+            // http://dev.mysql.com/doc/refman/5.7/en/delete.html
             buf.append(table.getAlias());
             addFrom(buf);
             addWhere(buf);
-            return buf.toString();
         }
     }
     
diff --git a/empire-db/src/main/java/org/apache/empire/dbms/oracle/DBCommandOracle.java b/empire-db/src/main/java/org/apache/empire/dbms/oracle/DBCommandOracle.java
index b7cf772..506f1f3 100644
--- a/empire-db/src/main/java/org/apache/empire/dbms/oracle/DBCommandOracle.java
+++ b/empire-db/src/main/java/org/apache/empire/dbms/oracle/DBCommandOracle.java
@@ -31,7 +31,6 @@
 import org.apache.empire.db.DBCommand;
 import org.apache.empire.db.DBIndex;
 import org.apache.empire.db.DBRowSet;
-import org.apache.empire.db.DBTable;
 import org.apache.empire.db.expr.column.DBAliasExpr;
 import org.apache.empire.db.expr.column.DBValueExpr;
 import org.apache.empire.db.expr.compare.DBCompareColExpr;
@@ -221,6 +220,7 @@
                 buf.append(usePreparedStatements ? "?" : String.valueOf(skipRows));
             }
         }
+        completeParamUsage();
     }
 
     @Override
@@ -242,30 +242,12 @@
         newParams[--newSize]=skipRows+limitRows;    
         return newParams;
     }
-    
-    /**
-     * Creates an Oracle specific update statement.
-     * If a join is required, this method creates a "MERGE INTO" expression 
-     */
-    @Override
-    public synchronized String getUpdate()
-    {
-        // No Joins: Use Default
-        if (joins==null || set==null)
-            return getSimpleUpdate();
-        else
-            return getUpdateWithJoins();
-    }
 
-    protected String getSimpleUpdate()
+    @Override
+    protected void addUpdateForTable(StringBuilder buf, DBRowSet table)
     {
-        resetParamUsage();
-        if (set == null)
-            return null;
-        StringBuilder buf = new StringBuilder("UPDATE ");
-        DBRowSet table =  set.get(0).getTable();
-        long context = CTX_FULLNAME;
         // Optimizer Hint
+        long context = CTX_FULLNAME;
         if (StringUtils.isNotEmpty(optimizerHint))
         {   // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */
             buf.append("/*+ ").append(optimizerHint).append(" */ ");
@@ -282,16 +264,14 @@
         addListExpr(buf, set, context, ", ");
         // Add Where
         addWhere(buf, context);
-        // done
-        return buf.toString();
     }
     
-    protected String getUpdateWithJoins()
+    @Override
+    protected void addUpdateWithJoins(StringBuilder buf, DBRowSet table)
     {
         // Generate Merge expression
-        resetParamUsage();
-        StringBuilder buf = new StringBuilder("MERGE INTO ");
-        DBRowSet table =  set.get(0).getTable();
+        buf.setLength(0);
+        buf.append("MERGE INTO ");
         table.addSQL(buf, CTX_FULLNAME|CTX_ALIAS);
         // join (only one allowed yet)
         DBColumnJoinExpr updateJoin = null;
@@ -393,8 +373,6 @@
         buf.append(")\r\nWHEN MATCHED THEN UPDATE ");
         buf.append("\r\nSET ");
         addListExpr(buf, mergeSet, CTX_DEFAULT, ", ");
-        // done
-        return buf.toString();
     }
         
     protected boolean isSetColumn(DBColumn col)
@@ -411,25 +389,25 @@
      * Creates an Oracle specific delete statement.
      * @return the delete SQL-Command
      */
+    
     @Override
-    public synchronized String getDelete(DBTable table)
+    protected void addDeleteForTable(StringBuilder buf, DBRowSet table)
     {
-        resetParamUsage();
-        StringBuilder buf = new StringBuilder("DELETE ");
-        if (optimizerHint != null)
+        if (StringUtils.isNotEmpty(optimizerHint))
         {   // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */
             buf.append("/*+ ").append(optimizerHint).append(" */ ");
         }
-        buf.append("FROM ");
-        table.addSQL(buf, CTX_FULLNAME);
-        // Set Expressions
-        if (where != null || having != null)
-        { // add where condition
-            buf.append("\r\nWHERE ");
-            if (where != null)
-                addListExpr(buf, where, CTX_NAME|CTX_VALUE, " AND ");
+        super.addDeleteForTable(buf, table);
+    }
+    
+    @Override
+    protected void addDeleteWithJoins(StringBuilder buf, DBRowSet table)
+    {
+        if (StringUtils.isNotEmpty(optimizerHint))
+        {   // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */
+            buf.append("/*+ ").append(optimizerHint).append(" */ ");
         }
-        return buf.toString();
+        super.addDeleteWithJoins(buf, table);
     }
 
 }
\ No newline at end of file
diff --git a/empire-db/src/main/java/org/apache/empire/dbms/postgresql/DBMSHandlerPostgreSQL.java b/empire-db/src/main/java/org/apache/empire/dbms/postgresql/DBMSHandlerPostgreSQL.java
index 6aa5d67..ad010e3 100644
--- a/empire-db/src/main/java/org/apache/empire/dbms/postgresql/DBMSHandlerPostgreSQL.java
+++ b/empire-db/src/main/java/org/apache/empire/dbms/postgresql/DBMSHandlerPostgreSQL.java
@@ -26,20 +26,23 @@
 import org.apache.empire.commons.ObjectUtils;
 import org.apache.empire.commons.StringUtils;
 import org.apache.empire.data.DataType;
+import org.apache.empire.db.DBColumn;
 import org.apache.empire.db.DBColumnExpr;
 import org.apache.empire.db.DBCommand;
 import org.apache.empire.db.DBDDLGenerator;
 import org.apache.empire.db.DBDDLGenerator.DDLActionType;
 import org.apache.empire.db.DBDatabase;
 import org.apache.empire.db.DBObject;
+import org.apache.empire.db.DBRowSet;
 import org.apache.empire.db.DBSQLScript;
 import org.apache.empire.db.DBTableColumn;
 import org.apache.empire.db.exceptions.EmpireSQLException;
+import org.apache.empire.db.exceptions.NoPrimaryKeyException;
 import org.apache.empire.db.exceptions.QueryNoResultException;
 import org.apache.empire.db.expr.column.DBValueExpr;
+import org.apache.empire.dbms.DBMSFeature;
 import org.apache.empire.dbms.DBMSHandler;
 import org.apache.empire.dbms.DBMSHandlerBase;
-import org.apache.empire.dbms.DBMSFeature;
 import org.apache.empire.dbms.DBSqlPhrase;
 import org.apache.empire.exceptions.InvalidArgumentException;
 import org.slf4j.Logger;
@@ -127,6 +130,41 @@
                 }    
             }
         }
+        
+        @Override
+        protected void addUpdateWithJoins(StringBuilder buf, DBRowSet table)
+        {
+            DBColumn[] keyColumns = table.getKeyColumns();
+            if (keyColumns==null || keyColumns.length==0)
+                throw new NoPrimaryKeyException(table);
+            // Join Update
+            table.addSQL(buf, CTX_NAME);
+            buf.append(" t0");
+            long context = CTX_DEFAULT;
+            // Set Expressions
+            buf.append("\r\nSET ");
+            addListExpr(buf, set, context, ", ");
+            // From clause
+            addFrom(buf);
+            // Add Where
+            buf.append("\r\nWHERE");
+            // key columns
+            for (DBColumn col : keyColumns)
+            {   // compare 
+                buf.append(" t0.");
+                col.addSQL(buf, CTX_NAME);
+                buf.append("=");
+                buf.append(table.getAlias());
+                buf.append(".");
+                col.addSQL(buf, CTX_NAME);
+            }
+            // more constraints
+            if (where!=null && !where.isEmpty())
+            {   // add where expression
+                buf.append("\r\n  AND ");
+                addListExpr(buf, where, context, " AND ");
+            }
+        }
     }
     
     private String databaseName;