Macromedia ColdFusion MX 7 Certified Developer Study Guide

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?

  1. The <cftransaction> tag can control isolation levels.

  2. Isolation levels affect performance.

  3. Isolation levels affect locking.

  4. ColdFusion enforces isolation when a database does not.

2:

What is the primary purpose of <cftransaction>?

  1. To commit all inserts to the database

  2. To make sure dirty reads do not take place

  3. To support commit and rollback features of a relational database system

  4. 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>

  1. Commits must be performed in a <cfif> block.

  2. Inner <cftransaction> is not terminated.

  3. Transaction tags can't be nested.

  4. Queries must be performed after commits are executed.

4:

Which isolation level is the least efficient?

  1. serializable

  2. repeatable_read

  3. read_uncommitted

  4. read_committed

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