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    <p>The general thumb rule in deciding whether to go for a PreparedStatement or not is:</p> <blockquote> <p>Use Prepared Statements, unless you have sufficient reason not to. Prepared Statements are compiled before execution therefore lending to better performance, and increased security against SQL injection as the database server takes care of the encoding of special characters.</p> </blockquote> <p>Going by the article that you have referenced, the list of reasons where I believe Prepared Statements are less useful than normal queries or stored procedures are:</p> <ul> <li><strong>One-time queries</strong>. If your application makes a single query to the database, and this is done infrequently compared to the other queries, it might not make sense to use a Prepared Statement in this case. The rationale is that the Prepared Statement must first be compiled and the 'compiled' form of the statement is cached for later use. For queries that are run infrequently, the compilation is an overhead. But still, it is preferable to use prepared statements, to avoid any SQL injection issues.</li> <li><strong>Data-intensive operations</strong>. Sometimes Prepared Statements are not as effective as stored procedures, especially when a sequence of operations need to be performed in the same transaction. When you have a business process that requires multiple selects, updates and deletes to be executed against a variety of tables, stored procedures are often better than a bunch of prepared statements executed one after the other. This performance penalty can turn serious as several network trips are made for the execution of multiple statements, which is considerably reduced when invoking a stored procedure. This effect is more pronounced in query batching where several objects are created and destroyed in a short duration of time. This often tends to be a contentious issue between database administrators and application developers, as this is an edge-case; DBAs will believe that the batching of operations is better performed via SPs, while application developers believe that PreparedStatements can handle it (its usually better to have all logic in one tier). It eventually boils down to the application on whether using SPs is an advantage or not.</li> <li><strong>Support for native database operations and types.</strong>. This might not hold good for MySQL, but in general the JDBC standard does not support all the operations supported by a database, and all the SQL/native/custom types supported by the database. This is more pronounced in the Oracle database (and possibly IBM DB2?), where programmers can create their own types, which require custom Java code to be written as the JDBC standard does not support User-Defined Types in the database. Similarly, other operations in the database need to not supported (as the MySQL document states) - one cannot create users (execute CREATE USER), modify user privileges (perform GRANT operations) etc. using a Prepared Statement. Stored procedures are better suited to this task, as they would have access to the native operation set of the database, either in a direct or indirect manner.</li> </ul>
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    1. POBest Practices with PreparedStatements; when to and when not to
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    1. USVineet Reynolds
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    1. COeven one time queries are compiled, but when you fire them, not when you prepare them. There are hardly any cases when you should not use prepared statements. Especially for security!
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      1. USPatrick Cornelissen
    2. CO@Patrick, there is no doubt that compilation occurs when ordinary Statement objects are also used. Use of PreparedStatement objects will result in precompilation of SQL queries (so long as the database driver supports it, which usually happens to be almost every driver encountered in day-to-day life). The difference between the two is that precompiled queries have placeholders for user inputs to be inserted into, with the insertion being done by the driver in conjunction with the database. So use of Statement objects is not the same as PreparedStatement although there is compilation involved.
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      1. USVineet Reynolds
    3. COAs for the cases where PreparedStatement cannot be used and the inherent security that is implied, PreparedStatements cannot ensure security when you have a statement like SELECT colA FROM tabB, where in colA happens to be user input; one simply cannot have a PreparedStatement declared as "SELECT ? FROM tabB". Precompilation has its limits.
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