Here you can add new fields computed through
row functions or aggregate functions.
If you not need to add any function, you can skip to next step.
You can specify any SQL function. You can enter any code you wish. Clearly the syntax
you use must be recognizable by the DBMS.
There are some placeholders <1>, <2>,
... these represents the
operand
fields that are used in the function. On the bottom
right is a "slider control" containing the operand to use. You can add any number
of operands. You can change anytime the operands by arrow icon near each operand.
The reason why we use placeholder is that you can save your function and reuse it
with different operands in other Data Sources.
You can
rename or
reorder your query
fields. The names you use here will be used in the query after the keyword "AS"
in the final query. Also the ordinal of the new query fields will reflect the order
which is indicated here. To change a query
field ordinal, just drag it or use the
arrow buttons, on the right side of the query-field treeview. The nodes in the query-field
treeview show the names of the query fields, and the subnode shows either the original
field or the SQL function. (Actually the program consider a simple field as particular
a function, say an "identity" function.)
When you define a function, one thing you should be particularly careful is to specify,
through the specific radio button, if it is an
aggregate function
(examples: of aggregate functions are: count, avg, sum, that is function which results
in a single aggregate value for all records with same dimensions) or it is a
row function (example: Quantity *
Price, which results always in one value
for each
record). The program need this information
because is letting you specify any script as SQL function. (The indication that
the specified function is an aggregate function will result, if necessary, in "Group
By" statements.)
If you wish you can test your function. In case, you can also browse the test code
and change if necessary.