About this task
Purpose
- Find items that contain specified minimum or maximum criteria
- Display attribute values for items that contain specified minimum or maximum criteria.
Assumptions
A Parts table has the following values for Order items.
id
|
partno
|
rev
|
i1
|
1
|
5
|
i1
|
1
|
2
|
i1
|
2
|
3
|
i1
|
3
|
1
|
i2
|
1
|
'1
|
i2
|
2
|
2
|
i2
|
5
|
1
|
Query Expressions
Several types of query expressions can be created using the min/max functionality.
A
|
listitems expression for normal TADB groups.
|
B
|
listitems expression for list TADB groups.
|
C
|
getvalues expression for normal TADB groups
|
D
|
getvalues expression for list TADB groups
|
-
listitems
expression for normal TADB Groups
listitems "orders","parts.rev=max()"
Where
Criteria
|
Is/are the:
|
orders
|
item type
|
Parts
|
Table name
|
rev
|
Revision number
|
max()
|
Maximum value
|
Procedure
-
The Query expression asks:
Which Order type item or items has/have the maximum revision number in the Parts table.
-
The answer is:
The maximum rev
in the table is 5. The Order item returned is i1
.
id
|
partno
|
rev
|
i1
|
1
|
5
|
i1
|
1
|
2
|
i1
|
2
|
3
|
i1
|
3
|
1
|
i2
|
1
|
1
|
i2
|
2
|
2
|
i2
|
5
|
1
|
-
listitems
expression for list TADB groups
listitems "orders","parts(partno='2').min(rev)"
Where
Criteria
|
Is/are the:
|
orders
|
item type
|
Parts
|
Table name
|
partno
|
Part number
|
2
|
Part number value to be included in the query.
|
min()
|
Minimum value
|
rev
|
Revision number
|
-
The Query expression asks:
Which Order items that have a part number of 2 have the minimum revision number?
-
The answer is:
i2
, part number 2
Two items have a part number of 2; the i2
item has the minimum revision number of those part numbers, which is 2.
id
|
partno
|
rev
|
i1
|
1
|
5
|
i1
|
1
|
2
|
i1
|
2
|
3
|
i1
|
3
|
1
|
i2
|
1
|
1
|
i2
|
2
|
2
|
i2
|
5
|
1
|
-
getvalues
expression for normal TADB groups
getvalues "i1","parts(rev=max()).partno"
Where
Criteria
|
Is/are the:
|
i1
|
Part id attribute value
|
Parts
|
Table name
|
rev
|
Revision number
|
max()
|
Maximum value
|
partno
|
Part number
|
-
The Query expression asks:
Get the part number of the i1
item that has the maximum rev
number.
-
The answer is:
1
partno 1 has the greatest rev
for item i1, which is 5.
id
|
partno
|
rev
|
i1
|
1
|
5
|
i1
|
1
|
2
|
i1
|
2
|
3
|
i1
|
3
|
1
|
i2
|
1
|
1
|
i2
|
2
|
2
|
i2
|
5
|
1
|
-
getvalues
expression for list TADB groups
getvalues "i1","parts(partno='1').min(rev).rev"
Where
Criteria
|
Is/are the:
|
i1
|
Part id attribute value
|
Parts
|
Table name
|
partno
|
Part number
|
1
|
Part number to be queried
|
min()
|
Minimum value
|
rev
|
Revision number attribute to return
|
-
The Query expression asks:
What is the minimum revision number for i1
items that have a 1 part number.
-
The answer is:
2
Records for item i1
with partno
1 have 2 rev values, 2 and 5. The minimum of those values is 2.
id
|
partno
|
rev
|
i1
|
1
|
5
|
i1
|
1
|
2
|
i1
|
2
|
3
|
i1
|
3
|
1
|
i2
|
1
|
1
|
i2
|
2
|
2
|
i2
|
5
|
1
|