l_shipmode
AIR
FOB
MAIL
RAIL
REG AIR
SHIP
TRUCK
l_shipmode
AIR
FOB
MAIL
RAIL
REG AIR
SHIP
TRUCK
l_shipmode
AIR
FOB
MAIL
RAIL
REG AIR
SHIP
TRUCK
l_shipmode
AIR
FOB
MAIL
RAIL
REG AIR
SHIP
TRUCK
l_shipmode
AIR
FOB
MAIL
RAIL
REG AIR
SHIP
TRUCK
t1_a	t1_b	t2_b
1	2	3
2	4	5
t1_a	t1_b	t2_b
1	2	3
2	4	5
t1_a	t1_b	t2_b
1	2	3
2	4	5
t1_a	t1_b	t2_b
1	2	3
2	4	5
t1_a	t1_b	t2_b
1	2	3
2	4	5
t1_a	t1_b	t2_b
2	4	5
t1_a	t1_b	t2_b
2	4	5
t1_a	t1_b	t2_b
1	2	3
2	4	5
3	6	NULL
t1_a	t1_b	t2_b
1	2	3
2	4	5
3	6	NULL
t1_a	t1_b	t2_b
1	2	3
2	4	5
3	6	NULL
t1_a	t1_b	t2_b
1	2	3
2	4	5
3	6	NULL
t1_a	t1_b	t2_b
1	2	3
2	4	5
3	6	NULL
t1_a	t1_b	t2_b
2	4	5
3	6	NULL
t1_a	t1_b	t2_b
2	4	5
3	6	NULL
a	b
2	4
3	6
a	b
1	2
2	4
a	b
2	4
3	6
a	b
1	2
a	b
3	6
a	b
2	4
3	6
a	b
2	4
3	6
a	b
3	6
a	SUM(b)
1	12
2	4
3	6
a	SUM(b)
1	12
a	SUM(b)
1	12
2	4
3	6
a	SUM(b)
1	12
a	SUM(b)
1	12
2	4
3	6
a	SUM(b)
1	12
2	4
3	6
a	SUM(b)
1	12
a	SUM(b)
1	12
2	4
3	6
a	SUM(b)
1	12
i
45
-45
10
i
46
-46
10
i
46
460
10
i
46
10
i
10