Sub-Query on sub-report

rbuser

Hi,

I have to execute an sql query as data source of a sub-report for each
master data source of my report (like master/detail relation but with sql
select instead of ttable)

Wich is the best event to run my sub-query ?
I try at the master TQuery level but it does'nt run.


Thanks
---
Serge Chelli
www.aceinformatique.com

nardmoseley

------------------------------------------------------
Tech Tip: Linking SQL Queries for Master/Detail Data
------------------------------------------------------

The following example shows two options for linking SQL queries to
create a master/detail relationship.

In this example, we are using Delphi's DBDemos data to create a
Customer/Order relationship. Thus we wish to link the Orders detail to
the Customer master.

I. Delphi Query Linking
------------------------

a. Set the detail TQuery.DataSource property to point to the master
query's TDataSource component.

b. In the SQL "Where" clause for the detail query use a ':' followed by
the linking field name from the master:

example
select *
from orders
where orders.CustNo = :CustNo

Now each time the master record position changes, the detail query will
automatically be refreshed with the correct result set.


II. RB DataPipeline Linking
-----------------------------

a. Set the detail DataPipeline.MasterDataPipeline to point to the master
DataPipeline.

b. Use the detail DataPipeline.MasterFieldLinks property to define the
linking relationship

c. In the SQL for the detail, retrieve all records and sort them by the
linking master field:

select *
from Orders
order by CustNo


Notes:

1. Using RB DataPipeline, each query is executed only a single time -
thus performance is much faster.

2. RB Professional and Enterprise Editions include a visual Data
environment for creating SQL queries, defining linking relationships,
and creating Ask-At-Runtime parameters. Using the RB tools you could
create the above linked queries in about 10 seconds.


--
Tech Support mailto:support@digital-metaphors.com
Digital Metaphors http://www.digital-metaphors.com

rbuser

Thanks, I will try it.
---
Serge Chelli
www.aceinformatique.com

"Nard Moseley (Digital Metaphors)" a ?crit dans