Welcome!

You will be redirected in 30 seconds or close now.

ColdFusion Authors: Yakov Fain, Jeremy Geelan, Maureen O'Gara, Nancy Y. Nee, Tad Anderson

Related Topics: ColdFusion

ColdFusion: Article

Faster and Safer Database Queries Using the <CFQUERYPARAM> Tag

Faster and Safer Database Queries Using the <CFQUERYPARAM> Tag

Databases and database access are fundamental elements of just about every ColdFusion application ever created. Database access makes applications real and live and dynamic and valuable, but it's also a major source of performance problems and a primary potential security target. In this article I discuss an oft overlooked tag, <CFQUERYPARAM>, designed to help address both potential problems.

Understanding <CFQUERYPARAM>
Database access (queries, insertions, updates, etc.) occurs by issuing SQL statements - plain text strings containing combinations of special statements, keywords, clauses, operators, and more. These strings are passed to the DBMS for processing (usually via a database driver) and are sometimes referred to as being ad hoc.

So far so good. But this is where it gets a little complicated. There are an infinite number of possible SQL statements (when you take into account the values passed to them), so once a DBMS receives a SQL statement, the DBMS must first analyze it to determine if it's valid, and then work out the best way to process it. Often, the process of parsing, validating, and analyzing the query (the term query refers to all SQL queries, even if they're not SELECT query operations) takes longer than processing the query itself.

Once the query is validated and analyzed, the DBMS tries to cache it so that the process won't need to be repeated unnecessarily. Simple queries without dynamic elements, like the following one, can be cached safely and easily:

SELECT *
FROM Customers

However, queries containing other clauses, like the one that follows, are a little harder to cache. After all, with an infinite number of variations it wouldn't be practical for the DBMS to cache them all:

SELECT *
FROM Customers
WHERE CustID=100

To cache this type of query the DBMS needs to know which part of the statement is dynamic and which is not, and that's where <CFQUERYPARAM> comes into play.

<CFQUERYPARAM> is a tag used within SQL statements (inside your <CFQUERY>). It replaces parameters (or any passed values) with placeholders that indicate the dynamic portions of a statement. For example:

<CFQUERY ...>
SELECT *
FROM Customers
WHERE CustID=<CFQUERYPARAM
CFSQLTYPE="CF_SQL_INTEGER"
VALUE="100">
</CFQUERY>

The <CFQUERYPARAM> tag replaces the passed value (100), and does two things: it defines the type of data that will be passed here and then passes the value to be used.

The actual SQL generated by this query will differ from DBMS to DBMS, but that's somewhat irrelevant. The important thing is that the DBMS knows that the query containing this block of text won't change (and can therefore be cached):

SELECT *
FROM Customers
WHERE CustID=

In DBMSese these variable portions of SQL statements, the ones bookmarked with <CFQUERYPARAM>, are known as bind parameters.

Specifying SQL Types
The data type passed to CFSQLTYPE tells the DBMS to expect data of a particular type. The supported types are:

 

  • CF_SQL_BIGINT
  • CF_SQL_BIT
  • CF_SQL_CHAR
  • CF_SQL_DATE
  • CF_SQL_DECIMAL
  • CF_SQL_DOUBLE
  • CF_SQL_FLOAT
  • CF_SQL_IDSTAMP
  • CF_SQL_INTEGER
  • CF_SQL_LONGVARCHAR
  • CF_SQL_MONEY
  • CF_SQL_MONEY4
  • CF_SQL_NUMERIC
  • CF_SQL_REAL
  • CF_SQL_REFCURSOR
  • CF_SQL_SMALLINT
  • CF_SQL_TIME
  • CF_SQL_TIMESTAMP
  • CF_SQL_TINYINT
  • CF_SQL_VARCHAR

    CFSQLTYPE is an optional at-tribute, but as a rule you should always specify an explicit type. The default value is CF_SQL_CHAR (a string) and is frequently not what you need.

    Increased Performance
    As already implied, the first benefit of using <CFQUERYPARAM> is increased performance. If the DBMS doesn't have to parse, analyze, and validate as much text, it'll be able to respond to requests quicker and more efficiently.

    It's common knowledge that stored procedures execute faster than ad hoc SQL statements. Part of the reason for this is that DBMSs cache the compiled stored procedures so they won't need to be processed repeatedly and unnecessarily. By using <CFQUERYPARAM> you get some of the benefits of stored procedures without having to write one.

    If you're interested in determining what the actual performance benefit is, turn on ColdFusion debugging output and try the queries both ways. As the DBMS load increases, so should the benefit of using bind parameters.

    Protecting from Malicious URL Tampering
    Note: As a rule I'm staunchly opposed to documenting security issues and how they're used, but as this particular vulnerability has been documented extensively (there are even Knowledge Base articles about it at www.macromedia.com) I'm making an exception this time.

    Another benefit to using <CF-QUERYPARAM> is security against malicious URL tampering. Consider the following example, an adaptation of the one used previously:

    SELECT *
    FROM Customers
    WHERE CustID=#URL.custid#

    Here a WHERE clause is populated dynamically using a URL parameter. This type of code is common and popular, and is used any time data drilldown of any kind is used. If the URL was:

    http://domain/path/file.cfm?custid=100

    the resulting SQL statement would be:

    SELECT *
    FROM Customers
    WHERE CustID=100

    But what if someone tampered with that URL so that it read:

    http://domain/path/file.cfm?custid=100;DELETE+Customers

    The resulting SQL would be:

    SELECT *
    FROM Customers
    WHERE CustID=100;
    DELETE Customers

    Depending on the DBMS being used, the <CFQUERY> could end up executing two statements - the SELECT and then DELETE Customers (which would promptly delete all data from the Customers table).

    Scared? You should be. As I mentioned earlier SQL statements are not just used for queries. They're also used to create and drop tables, create user logins, change DBMS passwords, set security levels, manage scheduled events, even create and drop entire databases. All features supported by your DBMS may be accessible this way.

    Before I go further I must point out that this is not a ColdFusion vulnerability; it's not even a bug or a hole. This is truly a feature - many DBMSs do indeed allow queries to contain more than a single operation; this is legal and by design.

    Of course, you should always be checking parameters before passing them to your DBMS. Passing URL parameters through unchecked is programmatic suicide. As such, you should already be using code like this:

    <CFIF IsDefined("URL.CustID")
    AND NOT IsNumeric(URL.CustID)>
    ... throw an error or something ...
    </CFIF>

    But <CFQUERYPARAM> provides one extra line of defense. If the previous tampered URL was passed to the following query, the value would be rejected and an error thrown. The CFSQLTYPE value also doubles as a datatype validation check, and values that don't match the type are rejected. Using <CFQUERYPARAM> you can secure yourself against one of the oldest and best-known hacks in the book.

    Note: This type of hack is one of the reasons you should never configure ColdFusion to use administrative accounts for database access (the SA account, for example). As a rule, the login specified in the data source definition should have just the access it needs and nothing more. If administrative access is not available to a login, then some of the more dangerous commands wouldn't be executable.

    Summary
    <CFQUERYPARAM> is not a new tag; it's been in ColdFusion since version 4.5. However, many developers have yet to use <CFQUERYPARAM>, primarily because they don't understand it. Most good DBMSs (including SQL Server and Oracle) support the use of bind parameters, but some don't. Be sure to read the docs on this tag, and then start plugging it into any new code and even existing apps. With increased performance and improved security you'd be remiss not to.

  • More Stories By Ben Forta

    Ben Forta is Adobe's Senior Technical Evangelist. In that capacity he spends a considerable amount of time talking and writing about Adobe products (with an emphasis on ColdFusion and Flex), and providing feedback to help shape the future direction of the products. By the way, if you are not yet a ColdFusion user, you should be. It is an incredible product, and is truly deserving of all the praise it has been receiving. In a prior life he was a ColdFusion customer (he wrote one of the first large high visibility web sites using the product) and was so impressed he ended up working for the company that created it (Allaire). Ben is also the author of books on ColdFusion, SQL, Windows 2000, JSP, WAP, Regular Expressions, and more. Before joining Adobe (well, Allaire actually, and then Macromedia and Allaire merged, and then Adobe bought Macromedia) he helped found a company called Car.com which provides automotive services (buy a car, sell a car, etc) over the Web. Car.com (including Stoneage) is one of the largest automotive web sites out there, was written entirely in ColdFusion, and is now owned by Auto-By-Tel.

    Comments (7) View Comments

    Share your thoughts on this story.

    Add your comment
    You must be signed in to add a comment. Sign-in | Register

    In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


    Most Recent Comments
    fgfrs 05/05/03 03:12:00 PM EDT

    b nv mn m

    Srinivasa 08/22/02 04:02:00 AM EDT
    Mo Hadi 02/13/02 12:07:00 PM EST

    There must be some kind of special set up necessary to do this, because I get the following error when after I change my code to use CFQUERYPARAM. Am I right?

    ODBC Error Code = S1C00 (Driver not capable)

    [Microsoft][ODBC SQL Server Driver]Optional feature not implemented

    David Shadovitz 02/12/02 03:28:00 PM EST

    Oops. CFDJ's code cut out my example CFML. Let's see if this gets through:

    WHERE id IN (<cfqueryparam value="#Form.ID#" cfsqltype="CF_SQL_INTEGER" list="yes">)

    David Shadovitz 02/12/02 03:25:00 PM EST

    As BF mentions, the default value of cfsqltype is CF_SQL_CHAR.

    If you get the error "ODBC Error Code = S1104 (Invalid precision value)", try using CF_SQL_VARCHAR instead.

    David Shadovitz 02/12/02 03:22:00 PM EST

    It's worth mentioning that CFQUERYPARAM can also be used with a list of values:

    ... WHERE ID IN ()

    Brad Howerter 02/12/02 01:06:00 PM EST

    Another benefit of is that you don't have to mess with preserveSingleQuotes().

    @ThingsExpo Stories
    With major technology companies and startups seriously embracing Cloud strategies, now is the perfect time to attend 21st Cloud Expo October 31 - November 2, 2017, at the Santa Clara Convention Center, CA, and June 12-14, 2018, at the Javits Center in New York City, NY, and learn what is going on, contribute to the discussions, and ensure that your enterprise is on the right path to Digital Transformation.
    The current age of digital transformation means that IT organizations must adapt their toolset to cover all digital experiences, beyond just the end users’. Today’s businesses can no longer focus solely on the digital interactions they manage with employees or customers; they must now contend with non-traditional factors. Whether it's the power of brand to make or break a company, the need to monitor across all locations 24/7, or the ability to proactively resolve issues, companies must adapt to...
    Artificial intelligence, machine learning, neural networks. We’re in the midst of a wave of excitement around AI such as hasn’t been seen for a few decades. But those previous periods of inflated expectations led to troughs of disappointment. Will this time be different? Most likely. Applications of AI such as predictive analytics are already decreasing costs and improving reliability of industrial machinery. Furthermore, the funding and research going into AI now comes from a wide range of com...
    "When we talk about cloud without compromise what we're talking about is that when people think about 'I need the flexibility of the cloud' - it's the ability to create applications and run them in a cloud environment that's far more flexible,” explained Matthew Finnie, CTO of Interoute, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
    Internet of @ThingsExpo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 21st Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago. All major researchers estimate there will be tens of billions devic...
    SYS-CON Events announced today that MobiDev, a client-oriented software development company, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. MobiDev is a software company that develops and delivers turn-key mobile apps, websites, web services, and complex software systems for startups and enterprises. Since 2009 it has grown from a small group of passionate engineers and business...
    SYS-CON Events announced today that GrapeUp, the leading provider of rapid product development at the speed of business, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Grape Up is a software company, specialized in cloud native application development and professional services related to Cloud Foundry PaaS. With five expert teams that operate in various sectors of the market acr...
    SYS-CON Events announced today that Ayehu will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on October 31 - November 2, 2017 at the Santa Clara Convention Center in Santa Clara California. Ayehu provides IT Process Automation & Orchestration solutions for IT and Security professionals to identify and resolve critical incidents and enable rapid containment, eradication, and recovery from cyber security breaches. Ayehu provides customers greater control over IT infras...
    In this presentation, Striim CTO and founder Steve Wilkes will discuss practical strategies for counteracting fraud and cyberattacks by leveraging real-time streaming analytics. In his session at @ThingsExpo, Steve Wilkes, Founder and Chief Technology Officer at Striim, will provide a detailed look into leveraging streaming data management to correlate events in real time, and identify potential breaches across IoT and non-IoT systems throughout the enterprise. Strategies for processing massive ...
    SYS-CON Events announced today that Cloud Academy named "Bronze Sponsor" of 21st International Cloud Expo which will take place October 31 - November 2, 2017 at the Santa Clara Convention Center in Santa Clara, CA. Cloud Academy is the industry’s most innovative, vendor-neutral cloud technology training platform. Cloud Academy provides continuous learning solutions for individuals and enterprise teams for Amazon Web Services, Microsoft Azure, Google Cloud Platform, and the most popular cloud com...
    In his session at Cloud Expo, Alan Winters, an entertainment executive/TV producer turned serial entrepreneur, presented a success story of an entrepreneur who has both suffered through and benefited from offshore development across multiple businesses: The smart choice, or how to select the right offshore development partner Warning signs, or how to minimize chances of making the wrong choice Collaboration, or how to establish the most effective work processes Budget control, or how to ma...
    SYS-CON Events announced today that Enzu will exhibit at SYS-CON's 21st Int\ernational Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Enzu’s mission is to be the leading provider of enterprise cloud solutions worldwide. Enzu enables online businesses to use its IT infrastructure to their competitive advantage. By offering a suite of proven hosting and management services, Enzu wants companies to focus on the core of their ...
    We build IoT infrastructure products - when you have to integrate different devices, different systems and cloud you have to build an application to do that but we eliminate the need to build an application. Our products can integrate any device, any system, any cloud regardless of protocol," explained Peter Jung, Chief Product Officer at Pulzze Systems, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA
    SYS-CON Events announced today that IBM has been named “Diamond Sponsor” of SYS-CON's 21st Cloud Expo, which will take place on October 31 through November 2nd 2017 at the Santa Clara Convention Center in Santa Clara, California.
    SYS-CON Events announced today that CA Technologies has been named "Platinum Sponsor" of SYS-CON's 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CA Technologies helps customers succeed in a future where every business - from apparel to energy - is being rewritten by software. From planning to development to management to security, CA creates software that fuels transformation for companies in the applic...
    Amazon started as an online bookseller 20 years ago. Since then, it has evolved into a technology juggernaut that has disrupted multiple markets and industries and touches many aspects of our lives. It is a relentless technology and business model innovator driving disruption throughout numerous ecosystems. Amazon’s AWS revenues alone are approaching $16B a year making it one of the largest IT companies in the world. With dominant offerings in Cloud, IoT, eCommerce, Big Data, AI, Digital Assista...
    Multiple data types are pouring into IoT deployments. Data is coming in small packages as well as enormous files and data streams of many sizes. Widespread use of mobile devices adds to the total. In this power panel at @ThingsExpo, moderated by Conference Chair Roger Strukhoff, panelists looked at the tools and environments that are being put to use in IoT deployments, as well as the team skills a modern enterprise IT shop needs to keep things running, get a handle on all this data, and deliver...
    In his session at @ThingsExpo, Eric Lachapelle, CEO of the Professional Evaluation and Certification Board (PECB), provided an overview of various initiatives to certify the security of connected devices and future trends in ensuring public trust of IoT. Eric Lachapelle is the Chief Executive Officer of the Professional Evaluation and Certification Board (PECB), an international certification body. His role is to help companies and individuals to achieve professional, accredited and worldwide re...
    With the introduction of IoT and Smart Living in every aspect of our lives, one question has become relevant: What are the security implications? To answer this, first we have to look and explore the security models of the technologies that IoT is founded upon. In his session at @ThingsExpo, Nevi Kaja, a Research Engineer at Ford Motor Company, discussed some of the security challenges of the IoT infrastructure and related how these aspects impact Smart Living. The material was delivered interac...
    IoT solutions exploit operational data generated by Internet-connected smart “things” for the purpose of gaining operational insight and producing “better outcomes” (for example, create new business models, eliminate unscheduled maintenance, etc.). The explosive proliferation of IoT solutions will result in an exponential growth in the volume of IoT data, precipitating significant Information Governance issues: who owns the IoT data, what are the rights/duties of IoT solutions adopters towards t...