One of the major benefits of using PreparedStatement is better performance. PreparedStatement gets pre-compiled. In database and their access plan is also cached in the database, which allows the database to execute parametric queries written using prepared statements much faster than normal queries because it has less work to do.
In order to get a performance benefit, it's worth noting to use only a parametrized version of SQL query and not with string concatenation. If you have been working in Java web applications you must be familiar with the infamous SQL Injection attacks, last year Sony got a victim of SQL injection and compromised several Sony play station user data.
In an SQL Injection attack, malicious users pass SQL meta-data combined with input which allowed them to execute SQL queries of their choice, If not validated or prevented before sending a query to the database. By using parametric queries and PreparedStatement you prevent many forms of SQL injection because all the parameters passed as part of the place-holder will be escaped automatically by JDBC Driver. At last PreparedStatement queries are more readable and secure than cluttered string concatenated queries.
Despite being very useful PreparedStatement also has few limitations:. Though there are some workarounds and ways to execute IN queries using PreparedStatement those are rather tricky or have a performance impact. Here are a few important points about PreparedStatement Class in Java, worth remembering:. PreparedStatement in Java allows you to write a parameterized query that gives better performance than the Statement class in Java. In the case of PreparedStatement, the Database uses an already compiled and defined access plan, this allows the prepared statement query to run faster than a normal query.
PreparedStatement allows you to write dynamic queries in Java. PreparedStatement is associated with java. Connection object, once you drop a connection all PreparedStatement associated with that connection will be dropped by Database. Index of placeholder or parameter starts with "1" and not with "0", which is a common cause of java. SQLException: Invalid column index. So in a PreparedStatement t of two placeholders, the first will be referred by index 1, and the second will be reference by index 2.
These were the reasons Why PreparedStatement in java is very popular and useful. You can still use the Statement object for test programmers but consider PreparedStatement before moving to production. Other Java tutorials you may like. Beginners guide to Generics in Java. How to use the Factory design pattern in Java with Example.
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Labels: best practices , core java , JDBC. March 24, at AM Javin iterate hashmpa java said March 24, at PM Anonymous said April 1, at PM Anonymous said PreparedStatement is not a class it is interface. October 21, at AM Anonymous said August 16, at PM Anonymous said PreparedStatement is a subinterafce not a class! The coffee names in the array coffees remain constant, so they do not need to be changed. In a real application, the values would probably be input from the user rather than from an initialized Java array.
Whereas executeQuery returns a ResultSet object containing the results of the query sent to the DBMS, the return value for executeUpdate is an int that indicates how many rows of a table were updated.
For instance, the following code shows the return value of executeUpdate being assigned to the variable n :. That update affected one row in the table, so n is equal to 1. When the method executeUpdate is used to execute a DDL statement, such as in creating a table, it returns the int 0.
Note that when the return value for executeUpdate is 0 , it can mean one of two things: 1 the statement executed was an update statement that affected zero rows, or 2 the statement executed was a DDL statement.
Copyright Sun Microsystems, Inc. All rights reserved. When to Use a PreparedStatement Object If you want to execute a Statement object many times, it will normally reduce execution time to use a PreparedStatement object instead.
Supplying Values for PreparedStatement Parameters You will need to supply values to be used in place of the question mark placeholders, if there are any, before you can execute a PreparedStatement object. Using the PreparedStatement object updateSales from the previous example, the following line of code sets the first question mark placeholder to a Java int with a value of updateSales. The next example sets the second placeholder parameter to the string " Colombian ": updateSales.
Using the PreparedStatement object updateSales , the following code fragment illustrates reusing a prepared statement after resetting the value of one of its parameters and leaving the other one the same: updateSales. Using a Loop to Set Values You can often make coding easier by using a for loop or a while loop to set values for input parameters.
Prepared Statement objects have some useful additional features than Statement objects. Instead of hard coding queries, PreparedStatement object provides a feature to execute a parameterized query.
Advantages of PreparedStatement Attention reader! Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. We can use the same PreparedStatement and supply with different parameters at the time of execution. Steps to use PreparedStatement 1. Create Connection to Database.
Set parameter values for type and position myStmt. It returns int type. Skip to content.
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