public void test_alter_first() throws Exception {
String sql = "ALTER TABLE dbo.doc_exc ADD column_b VARCHAR(20) NULL "//
+ " CONSTRAINT exb_unique UNIQUE ;";
SQLServerStatementParser parser = new SQLServerStatementParser(sql);
SQLStatement stmt = parser.parseStatementList().get(0);
parser.match(Token.EOF);
SQLServerSchemaStatVisitor visitor = new SQLServerSchemaStatVisitor();
stmt.accept(visitor);
System.out.println("Tables : " + visitor.getTables());