SELECT * 
FROM test_values t1
WHERE t1.karts_sost =  2  and
      t1.karts_date = (select max(karts_date)
                       from test_values t2
                       where t2.kart_id=t1.kart_id)

CREATE TABLE test_values (id_karts_history integer NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE,karts_sost integer,kart_id integer,karts_date date);

INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('100', '2', NULL);

INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('101', '1', NULL);
INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('101', '2', '2009-09-01');
INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('101', '2', '2009-08-01');
INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('101', '3', '2009-08-13');

INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('102', '2', NULL);

INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('103', '1', NULL);
INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('103', '3', '2009-08-25');

id_karts_history    |	karts_id    | 	karts_sost   |	karts_date
---------------------------------------------------------------------
	1            |	   100	    |        2	     |   NULL
---------------------------------------------------------------------
	3            |	   101	    |        2	     |   2009-09-01
---------------------------------------------------------------------
	6            |	   102	    |        2	     |   NULL
---------------------------------------------------------------------

id_karts_history    |	karts_id    | 	karts_sost   |	karts_date
---------------------------------------------------------------------
	1            |	   100	    |        2	     |   NULL
---------------------------------------------------------------------
	3            |	   101	    |        2	     |   2009-09-01
---------------------------------------------------------------------
	6            |	   102	    |        2	     |   NULL
---------------------------------------------------------------------
	8            |	   103	    |        3	     |   2009-08-25
---------------------------------------------------------------------

INSERT INTO test_values('kart_id', 'karts_sost', 'karts_date') VALUES ('101', '2', NULL);

CREATE TABLE [TPARTS] 
(
    [DOC_ID] ,
    [BLOCK_ID] ,
    [TEXT] ,
    [VRS_DATE] ,
    [BLOCK_UID] 
);

INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '1', 'Заголовок документа 100', null,  101 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '2', 'Абзац 1', null,  102 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '3', 'Абзац 2 в начальной редакции', null,  103 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '3', 'Абзац 2 в редакции от 2010-11-23', '20101123',  106 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('999', '1', 'Заголовок документа 999', null,  107 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('999', '2', 'Абзац 1 документа 999 в редакции 2010-06-06', '20100606',  108 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '5', 'Подпись документа 100', null,  109 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '4', 'Абзац 3 документа 100', null,  110 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '3', 'Абзац 2 в редакции 2010-06-06', '20100606',  104 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('100', '3', 'Абзац 2 в редакции 2010-02-02', '20100202',  105 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('999', '3', 'Подпись документа 999', null,  122 );
INSERT INTO [TPARTS] ([DOC_ID], [BLOCK_ID], [TEXT], [VRS_DATE], [BLOCK_UID]) VALUES ('999', '2', 'Абзац 1 документа 999 в начальной редакции', null,  100 ); 

SELECT *
FROM TPARTS t1
WHERE t1.DOC_ID = '100' and
      (t1.VRS_DATE is null or
       t1.VRS_DATE = (select max(VRS_DATE)
                        from TPARTS t2
                        where t2.BLOCK_ID=t1.BLOCK_ID)
      ) ORDER BY BLOCK_ID;

SELECT *
FROM TPARTS t1
WHERE DOC_ID='100' and
t1.VRS_DATE = (select max(VRS_DATE)
                        from TPARTS t2
                        where t2.BLOCK_ID=t1.BLOCK_ID
                        )
union
SELECT *
FROM TPARTS t1
WHERE DOC_ID='100' and 
      not exists (select  1 
                  from TPARTS t2
                  where t2.BLOCK_ID=t1.BLOCK_ID and VRS_DATE is not null)                 
ORDER BY BLOCK_ID;   

UPDATE TPARTS SET VRS_DATE='20000101' WHERE (VRS_DATE IS NULL) or (VRS_DATE='');

SELECT *
FROM TPARTS t1
WHERE DOC_ID='100' 
and t1.VRS_DATE = (select max(VRS_DATE)
                        from TPARTS t2
                        where t2.BLOCK_ID=t1.BLOCK_ID)