Say I have a table of companies, and a table of industries (like
automobiles, steel, computers, etc..) A company may be involved in
industries, so there's a third table- a mapping table- which just keys a
company to a specific industry. This table can have multiple rows for a
single company, since some companies can be involved in multiple industries.
Now when I display Companies in a DataGrid, I want a column that prints out
all the industries it is involved in- in a comma-separated string. So one
column's data might look like "Automobile s, Machine Tools, Aeronautics" if
there are 3 rows for that company mapping it to each of those industries.
Now the trick is, how would I accomplish this just using DataTable
expression? No real SQL, just whatever the DataColumn expression syntax has
to offer... is it possible?
1  1715 
The DataColumn expression syntax is just for processing the data in that
column in that table, it isn't suited for retrieving data from other tables.
You'll have to do that in code yourself, probably after you fill your
dataset you could add a new calculated column, loop through the rows,
retrieve the industries data and synthetically create the value for the
column.
--
John Wood
Blog: http://spaces.msn.com/members/johnwood/
"MrNobody" <Mr******@discu ssions.microsof t.com> wrote in message
news:ED******** *************** ***********@mic rosoft.com... Say I have a table of companies, and a table of industries (like
automobiles, steel, computers, etc..) A company may be involved in
industries, so there's a third table- a mapping table- which just keys a
company to a specific industry. This table can have multiple rows for a
single company, since some companies can be involved in multiple
industries.
Now when I display Companies in a DataGrid, I want a column that prints
out all the industries it is involved in- in a comma-separated string. So one
column's data might look like "Automobile s, Machine Tools, Aeronautics"
if there are 3 rows for that company mapping it to each of those industries.
Now the trick is, how would I accomplish this just using DataTable
expression? No real SQL, just whatever the DataColumn expression syntax
has to offer... is it possible? This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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last post by:
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------------
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