begin implementation of oracle recursive queries

Author: wumpz

src/main/javacc/net/sf/jsqlparser/parser/JSqlParserCC.jj

@@ -253,6 +253,8 @@ TOKEN: /* SQL Keywords. prefixed with K_ to avoid name clashes */
 |	<K_FOREIGN:"FOREIGN">
 |	<K_CONSTRAINT:"CONSTRAINT">
 |	<K_REFERENCES:"REFERENCES">
+|	<K_START:"START">
+|	<K_CONNECT:"CONNECT">
 }
 
 
@@ -619,6 +621,7 @@ PlainSelect PlainSelect():
       joins=JoinsList() ]
 
     [ where=WhereClause() { plainSelect.setWhere(where); }]
+	[ OracleHierarchicalQueryClause() ]
     [ groupByColumnReferences=GroupByColumnReferences() { plainSelect.setGroupByColumnReferences(groupByColumnReferences); }]
     [ having=Having() { plainSelect.setHaving(having); }]
 	[LOOKAHEAD(2) orderByElements = OrderByElements()	{ 		 plainSelect.setOrderByElements(orderByElements);	}   ]
@@ -1078,6 +1081,14 @@ Expression WhereClause():
     { return retval; }
 }
 
+Expression OracleHierarchicalQueryClause(): {}
+{
+	[ <K_START> <K_WITH>  AndExpression() ]
+	<K_CONNECT> <K_BY> [ "NOCYCLE" ]  AndExpression()
+
+	{ return null; }
+}
+
 
 List<Expression> GroupByColumnReferences():
 {

src/test/java/net/sf/jsqlparser/test/select/SelectTest.java

@@ -1117,4 +1117,19 @@ public void testNamedParameter2() throws JSQLParserException {
         assertEquals("param2", namedParameter2.getName());
         assertEquals("param3", namedParameter3.getName());
     }
+	
+	public void testOracleHierarchicalQuery() throws JSQLParserException {
+		String stmt= "SELECT last_name, employee_id, manager_id FROM employees CONNECT BY employee_id = manager_id ORDER BY last_name";
+		assertSqlCanBeParsedAndDeparsed(stmt);
+	}
+	
+	public void testOracleHierarchicalQuery2() throws JSQLParserException {
+		String stmt= "SELECT employee_id, last_name, manager_id FROM employees CONNECT BY PRIOR employee_id = manager_id";
+		assertSqlCanBeParsedAndDeparsed(stmt);
+	}
+	
+	public void testOracleHierarchicalQuery3() throws JSQLParserException {
+		String stmt= "SELECT last_name, employee_id, manager_id, LEVEL FROM employees START WITH employee_id = 100 CONNECT BY PRIOR employee_id = manager_id ORDER SIBLINGS BY last_name";
+		assertSqlCanBeParsedAndDeparsed(stmt);
+	}
 }