string type rows are missed in segment v2

[kangpinghuang]

for table:

CREATE TABLE test (
k1 tinyint(4) NOT NULL COMMENT "",
k2 smallint(6) NOT NULL COMMENT "",
k3 int(11) NOT NULL COMMENT "",
k4 bigint(20) NOT NULL COMMENT "",
k5 decimal(9, 3) NOT NULL COMMENT "",
k6 char(5) NOT NULL COMMENT "",
k10 date NOT NULL COMMENT "",
k11 datetime NOT NULL COMMENT "",
k7 varchar(20) NOT NULL COMMENT "",
k8 double MAX NOT NULL COMMENT "",
k9 float SUM NOT NULL COMMENT ""
) ENGINE=OLAP
AGGREGATE KEY(k1, k2, k3, k4, k5, k6, k10, k11, k7)
COMMENT "OLAP"
PARTITION BY RANGE(k1)
(PARTITION p1 VALUES [("-128"), ("-64")),
PARTITION p2 VALUES [("-64"), ("0")),
PARTITION p3 VALUES [("0"), ("64")),
PARTITION p4 VALUES [("64"), (MAXVALUE)))
DISTRIBUTED BY HASH(k1) BUCKETS 5
PROPERTIES (
"storage_type" = "COLUMN",
"replication_num" = "1"
);

the data is as follow:

1 1989 1001 11011902 123.123 true 1989-03-21 1989-03-21 13:00:00 wangjing04 0.1 6.333
2 1986 1001 11011903 1243.5 false 1901-12-31 1989-03-21 13:00:00 wangyu14 20.268 789.25
3 1989 1002 11011905 24453.325 false 2012-03-14 2000-01-01 00:00:00 yuanyuan06 78945 3654.0
4 1991 3021 -11011907 243243.325 false 3124-10-10 2015-03-13 10:30:00 yanhuicang01 2.06 -0.001
5 1985 5014 -11011903 243.325 true 2015-01-01 2015-03-13 12:36:38 duyunkai@123 -0.000 -365
6 32767 3021 123456 604587.000 true 2014-11-11 2015-03-13 12:36:38 yanhuiacng01 0.1 80699
7 -32767 1002 7210457 3.141 false 1988-03-21 1901-01-01 00:00:00 jingyong 0.0 6058
8 255 2147483647 11011920 -0.123 true 1989-03-21 9999-11-11 12:12:00 wangjing05 987456.123 12.14
9 1991 -2147483647 11011902 -654.654 true 1991-08-11 1989-03-21 13:11:00 wangjing04 0.000 69.123
10 1991 5014 9223372036854775807 -258.369 false 2015-04-02 2013-04-02 15:16:52 wangyu14 -123456.54 0.235
11 1989 25699 -9223372036854775807 0.666 true 2015-04-02 1989-03-21 13:11:00 yuanyuan06 -987.001 4.336
12 32767 -2147483647 9223372036854775807 243.325 false 1991-08-11 2013-04-02 15:16:52 liuyuantuo -564.898 3.141592654
13 -32767 2147483647 -9223372036854775807 100.001 false 2015-04-02 2015-04-02 00:00:00 weike01 123.456 3.141592653
14 255 103 11011902 -0.000 false 2015-04-02 2015-04-02 00:00:00 3.141592654 2.036
15 1992 3021 11011920 0.00 true 9999-12-12 2015-04-02 00:00:00 3.141592653 20.456

there are 7 records which k6="true", but the query below:
select * from test where k6="true";
returns 6 records.

this bug is found by regression test.

[kangpinghuang]

the reason is zone map of segment is wrong and some segments are filtered incorrectly.