MACROMEDIA COLFUSION MX 7 - INSTALLING AND USING COLDFUSION MX, Справочник

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cftransaction 427
Usage
If you do not specify a value for the
action
attribute, automatic transaction processing proceeds
as follows:
•
If the
cfquery
operations within the transaction block complete without an error, the
transaction is committed.
•
If a
cfquery
tag generates an error within a
cftransaction
block, all
cfquery
operations in
the transaction roll back.
If you do not specify a value for the
isolation
attribute, ColdFusion uses the default isolation
level for the associated database.
Using CFML error handling and the
action
attribute, however, you can also explicitly control
whether a transaction is committed or rolled back, based on the success or failure of the database
query. Within a transaction block, you can do the following:
•
Commit a database transaction by nesting the
<cftransaction action = "commit"/>
tag
within the block
•
Roll back a transaction by nesting the
<cftransaction action = "rollback"/>
tag within
the block
(In these examples, the slash is alternate syntax that is the equivalent of an end tag.)
Within a transaction block, you can write queries to more than one database, but you must
commit or roll back a transaction to one database before writing a query to another.
To control how the database engine performs locking during the transaction, use the
isolation
attribute.
Example
<p>CFTRANSACTION can be used to group multiple queries that use CFQUERY
into one business event. Changes to data that is requested by the queries
are not committed to the datasource until all actions within the transaction
block have executed successfully.
<p>This a view-only example.
<!---
<cftransaction>
<cfquery name='makeNewCourse' datasource='Snippets'>
INSERT INTO Courses
(Number, Descript)
VALUES
('#myNumber#', '#myDescription#')
</cfquery>
<cfquery name='insertNewCourseToList' datasource='Snippets'>
INSERT INTO CourseList
(CorNumber, CorDesc, Dept_ID,
CorName, CorLevel, LastUpdate)
VALUES
('#myNumber#', '#myDescription#', '#myDepartment#',
'#myDescription#', '#myCorLevel#', #Now()#)
</cfquery>
</cftransaction>
--->