Now it is time to present functionality of the described above components in
a very simple example. Our data source will comprise of a text file containing
entries to be used in order to modify content of the Shippers table in the Northwind
database, in the following, semicolon-separated format:
Update;1;Super Speedy Express;(503) 555-9831
Update;2;Offshored Package;91 (123) 555-3199
Insert;4;Road Runner;(503) 555-1234
Insert;5;Speedy Gonzalez;(503) 555-4321
Delete;4;Road Runner;(503) 555-1234
Copy the five rows listed above to a text file and save it, (location and
name are not relevant). As you can easily guess, the first field indicates the
type of change to be applied, the second is the record (row) identifier, and
the last two (Company Name and Company Phone) are used to create a new entry or
update an existing one (they are obviously irrelevant in case of deletion). The
row number 4 will be inserted and then shortly after deleted (purely for
demonstration purposes). Note that we cannot simply delete already existing
three Shippers rows because of the referential integrity rules. After the DTS
task is completed, the first two rows should be modified and the fourth row
should be added (with ShipperID identity column value set to 5).
We will use Shippers as our binding (as well as target) table. Since source
and binding tables require separate connections, we will start by defining
them. The first one will be of Text File (Source) type (you can locate it in
the Connection menu or toolbar of the DTS Designer window). Specify the name of
the file you just saved, make sure that you select Delimited file format, and
choose semicolon as the column delimiter. Our target connection will be based
on standard Microsoft OLE DB Provider for SQL Server pointing to the Northwind
database on your test SQL Server.
Once connections are created, select the Data Driven Query task from the
Task menu of the DTS Designer (or the toolbar area). Make sure that the Text
File (Source) connection is listed on the Source tab (you can use the Preview
button to verify that our sample data is properly interpreted). On the Bindings
tab, choose the Northwind database connection and Shippers table. Delete
default transformation on the Transformation tab. Click on the New button to
define a new one and choose the ActiveX Script entry from the Create New
Transformation dialog box. This will trigger display of the Transformation
Options dialog box. On the Source Columns tab, select all columns (Col001 to
Col004) and verify that the Binding Columns tab contains all entries from the
binding table. On the General tab, click on the Properties button, which will
display the following, automatically generated transformation script :
Function Main()
DTSDestination("ShipperID") = DTSSource("Col001")
DTSDestination("CompanyName") = DTSSource("Col002")
DTSDestination("Phone") = DTSSource("Col003")
Main = DTSTransformstat_InsertQuery
End Function
Replace it with the custom one, which will take into consideration the first
column to determine the type of query to be invoked:
Function Main()
Select Case UCase(Trim(DTSSource("Col001")))
Case "UPDATE"
DTSDestination("ShipperID") = DTSSource("Col002")
DTSDestination("CompanyName") = DTSSource("Col003")
DTSDestination("Phone") = DTSSource("Col004")
Main = DTSTransformstat_UpdateQuery
Case "INSERT"
DTSDestination("ShipperID") = DTSSource("Col002")
DTSDestination("CompanyName") = DTSSource("Col003")
DTSDestination("Phone") = DTSSource("Col004")
Main = DTSTransformstat_InsertQuery
Case "DELETE"
DTSDestination("ShipperID") = DTSSource("Col002")
Main = DTSTransformstat_DeleteQuery
Case ELSE
Main = DTSTransformstat_UserQuery
End Select
End Function
Confirm your changes by clicking on the OK buttons and return to the Data
Driven Query Task Properties dialog box. On the queries tab, fill out the
content of Insert, Update, and Delete query types with the following TSQL
statements (one per type):
INSERT Shippers ([CompanyName],[Phone])
VALUES (?, ?)
UPDATE Shippers
SET CompanyName = ?, Phone = ?
WHERE (ShipperID = ?)
DELETE FROM Shippers
WHERE ShipperID = ?
For each statement, click on the Parse/Show parameters and verify that each
parameter corresponds to an appropriate column from the target table
(Shippers). Default mapping between parameters and destination columns can be
modified by clicking on individual destination columns in the lower portion of
the dialog box (this will be necessary for the Insert and Update statements).
Finally, click on OK to close the Data Driven Query Task Properties dialog box,
save your package, and execute it. You can verify that the content of the
Shippers table has changed as expected using standard methods (Query Analyzer
or Enterprise Manager):
1 Super Speedy Express (503) 555-9831
2 Offshored Package 91 (123) 555-3199
3 Federal Shipping (503) 555-9931
5 Speedy Gonzalez (503) 555-4321
This simple exercise should give you the basis for creating your own
packages including Data Driven Query task. For other examples, refer to the
Books Online. We will complete our coverage of DTS tasks in the next article.
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