merge oracle hierarchical syntax into main

Author: wumpz

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

@@ -257,6 +257,11 @@ TOKEN: /* SQL Keywords. prefixed with K_ to avoid name clashes */
 |	<K_REFERENCES:"REFERENCES">
 |	<K_CHARACTER:"CHARACTER">
 |	<K_VARYING:"VARYING">
+|	<K_START:"START">
+|	<K_CONNECT:"CONNECT">
+|	<K_PRIOR:"PRIOR">
+|   <K_NOCYCLE:"NOCYCLE">
+|	<K_SIBLINGS:"SIBLINGS">
 }
 
 

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

@@ -1129,6 +1129,11 @@ public void testNamedParameter2() throws JSQLParserException {
         assertEquals("param3", namedParameter3.getName());
     }
 
+	public void testComplexUnion1() throws IOException, JSQLParserException {
+		String stmt = "(SELECT 'abc-' || coalesce(mytab.a::varchar, '') AS a, mytab.b, mytab.c AS st, mytab.d, mytab.e FROM mytab WHERE mytab.del = 0) UNION (SELECT 'cde-' || coalesce(mytab2.a::varchar, '') AS a, mytab2.b, mytab2.bezeichnung AS c, 0 AS d, 0 AS e FROM mytab2 WHERE mytab2.del = 0)";
+		assertSqlCanBeParsedAndDeparsed(stmt);
+	}
+	
 	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);