Use of dynamic columns, where clauses, etc.

[Jon Alsager <JAlsager@ISIF.STATE.ID.US>]

Hi, all...

Can someone please explain to me why a program would have the following:

let $s1 = 'column_name1||column_name2'

Then later in the program...

begin-select
[$s1]   &s1=char

from table_name
where...

The value of $s1 never changes.  I guess what I don't understand is, what is
gained by using a dynamic column variable that is defined by a literal that
never changes.  Is this a performance thing?  Why not just type
column_name1||column_name2 directly into the begin-select?

I've also seen it in a where clause, such as:

let $where_clause = 'where column_name1 = column_name2'
let $where_clause = $where_clause||'and column_flag = ''Y'''

begin-select
column1
column2

from table_name
[$where_clause]

Here again, nothing in $where_clause ever changes after the LETs.

One thing I was told by a Brio rep was that if any dynamic variable is used
in a begin-select, SQR treats all treats all columns as charactor is it
apparently is not able to correctly resolve their datatypes.

Anything anyone can offer to help me understand this would be much
appreciated!

Jon