Summary

Transactions are an integral part of any relational database. You control transactions through a ColdFusion application by using the <cftransaction> tag. This tag has no required attributes but controls isolation levels through the isolation attribute, and can conditionally commit or roll back parts of a transaction through the action attribute. Transactions cannot be spanned across pages.

Sample Questions

1:	Which of the following statements are true? The <cftransaction> tag can control isolation levels. Isolation levels affect performance. Isolation levels affect locking. ColdFusion enforces isolation when a database does not.
2:	What is the primary purpose of <cftransaction>? To commit all inserts to the database To make sure dirty reads do not take place To support commit and rollback features of a relational database system To supplement the <cflock> tag in locking database records
3:	What is wrong with the following code? <cftransaction> <cfquery datasource....> ... </cfquery> <cftransaction action="commit"> </cftransaction> Commits must be performed in a <cfif> block. Inner <cftransaction> is not terminated. Transaction tags can't be nested. Queries must be performed after commits are executed.
4:	Which isolation level is the least efficient? serializable repeatable_read read_uncommitted read_committed