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    <p>First of all, you should <em>NEVER</em> do SQL command compositions on a client app like this, <em>that's</em> what SQL Injection is. (Its OK for an admin tool that has no privs of its own, but not for a shared use application).</p> <p>Secondly, yes, a parametrized call to a Stored procedure is both cleaner and safer. </p> <p><em>However</em>, as you will need to use Dynamic SQL to do this, you still do not want to include the passed string in the text of the executed query. Instead, you want to used the passed string to look up the names of the <em>actual</em> tables that the user should be allowed to query in the way.</p> <p>Here's a simple naive example:</p> <pre><code>CREATE PROC spCountAnyTableRows( @PassedTableName as NVarchar(255) ) AS -- Counts the number of rows from any non-system Table, *SAFELY* BEGIN DECLARE @ActualTableName AS NVarchar(255) SELECT @ActualTableName = QUOTENAME( TABLE_NAME ) FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = @PassedTableName DECLARE @sql AS NVARCHAR(MAX) SELECT @sql = 'SELECT COUNT(*) FROM ' + @ActualTableName + ';' EXEC(@SQL) END </code></pre> <hr> <p>Some have fairly asked why this is safer. Hopefully, little Bobby Tables can make this clearer:</p> <p><img src="https://imgs.xkcd.com/comics/exploits_of_a_mom.png" alt="alt text"></p> <hr> <p>Answers to more questions: </p> <ol> <li><p>QUOTENAME alone is not guaranteed to be safe. MS encourages us to use it, but they have not given a guarantee that it cannot be out-foxed by hackers. FYI, real Security is all about the guarantees. The table lookup with QUOTENAME, is another story, it's unbreakable.</p></li> <li><p>QUOTENAME is not strictly necessary for this example, the Lookup translation on INFORMATION_SCHEMA alone is normally sufficient. QUOTENAME is in here because it is good form in security to include a complete and correct solution. QUOTENAME in here is actually protecting against a distinct, but similar potential problem know as <em>latent injection</em>.</p></li> </ol>
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    1. POHow should I pass a table name into a stored proc?
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    1. POHow should I pass a table name into a stored proc?
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    1. COAlthough I don't like using dynamic SQL, this seems like the best option to solve the issue at hand. +1
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    2. COSorry, I can't get why is it SAFER? Safer in what regard? There's no guarantee that that table exists, i.e. we still can get a syntax error when doing EXEC(@SQL).
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    3. COHmm...I don't know about your first statement...maybe you're using a different definition for SQL Injection than I am. Certainly, if I took that option, I would be "injecting" text into a SQL Server query, but I'm using it in the pejoritive sense where a user modifies something on purpose to send something to SQL that shouldn't be sent. I don't have to worry about that, since the user never sees or has access to any of the parameters that would be being sent.
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