Prepared Statement Get Generated Keys Select

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  • Statement.executeUpdate(sql-statement, Statement.RETURNGENERATEDKEYS); The following forms are valid only if the data source supports SELECT FROM INSERT statements. Sql-statement can be a single-row INSERT statement or a multiple-row INSERT statement. With the first form, you specify the names of the columns for which you want automatically.
  • Mysqli-prepare returns a so-called statement object which is used for subsequent operations eg execute, bindparam, storeresult, bindresult, fetch, etc. The statement object has private properties which update as each statement operation is carried out.

Prepared statements reduce parsing time as the preparation on the query is done only once (although the statement is executed multiple times) Bound parameters minimize bandwidth to the server as you need send only the parameters each time, and not the whole query; Prepared statements are very useful against SQL injections, because parameter. The following are Jave code examples for showing how to use getGeneratedKeys of the java.sql.PreparedStatement class. You can vote up the examples you like. Your votes will be used in our system to get more good examples. If you can't use RETURNGENERATEDKEYS, use another statement (a query this time) to do. SELECT lastinsertid Make sure that you definitely have an auto-increment primary key column in that table. In this example, while creating an instance of PreparedStatement, we have passed 2 arguments. 1st is the query itself and 2 nd is “Statement.RETURNGENERATEDKEYS“, which will help us to get the primary key value of the new row. The below code is used to provide parameters for Insert Query. Its value will be set by calling the setter methods of PreparedStatement. Why use PreparedStatement? Improves performance: The performance of the application will be faster if you use PreparedStatement interface because query is compiled only once. How to get the instance of PreparedStatement?

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Prepared Statement Get Generated Keys Select In One

Once a connection is obtained we can interact with the database. The JDBC Statement, CallableStatement, and PreparedStatement interfaces define the methods and properties that enable you to send SQL or PL/SQL commands and receive data from your database.

They also define methods that help bridge data type differences between Java and SQL data types used in a database.

The following table provides a summary of each interface's purpose to decide on the interface to use.

Prepared Statement Get Generated Keys Select 1

InterfacesRecommended Use
StatementUse this for general-purpose access to your database. Useful when you are using static SQL statements at runtime. The Statement interface cannot accept parameters.
PreparedStatementUse this when you plan to use the SQL statements many times. The PreparedStatement interface accepts input parameters at runtime.
CallableStatementUse this when you want to access the database stored procedures. The CallableStatement interface can also accept runtime input parameters.

The Statement Objects

Creating Statement Object

Before you can use a Statement object to execute a SQL statement, you need to create one using the Connection object's createStatement( ) method, as in the following example −

Once you've created a Statement object, you can then use it to execute an SQL statement with one of its three execute methods.

  • boolean execute (String SQL): Returns a boolean value of true if a ResultSet object can be retrieved; otherwise, it returns false. Use this method to execute SQL DDL statements or when you need to use truly dynamic SQL.

  • int executeUpdate (String SQL): Returns the number of rows affected by the execution of the SQL statement. Use this method to execute SQL statements for which you expect to get a number of rows affected - for example, an INSERT, UPDATE, or DELETE statement.

  • ResultSet executeQuery (String SQL): Returns a ResultSet object. Use this method when you expect to get a result set, as you would with a SELECT statement.

Closing Statement Object

Just as you close a Connection object to save database resources, for the same reason you should also close the Statement object.

A simple call to the close() method will do the job. If you close the Connection object first, it will close the Statement object as well. However, you should always explicitly close the Statement object to ensure proper cleanup.

For a better understanding, we suggest you to study the Statement - Example tutorial.

The PreparedStatement Objects

The PreparedStatement interface extends the Statement interface, which gives you added functionality with a couple of advantages over a generic Statement object.

This statement gives you the flexibility of supplying arguments dynamically.

Creating PreparedStatement Object

All parameters in JDBC are represented by the ? symbol, which is known as the parameter marker. You must supply values for every parameter before executing the SQL statement.

The setXXX() methods bind values to the parameters, where XXX represents the Java data type of the value you wish to bind to the input parameter. If you forget to supply the values, you will receive an SQLException.

Each parameter marker is referred by its ordinal position. The first marker represents position 1, the next position 2, and so forth. This method differs from that of Java array indices, which starts at 0.

All of the Statement object's methods for interacting with the database (a) execute(), (b) executeQuery(), and (c) executeUpdate() also work with the PreparedStatement object. However, the methods are modified to use SQL statements that can input the parameters.

Closing PreparedStatement Object

Just as you close a Statement object, for the same reason you should also close the PreparedStatement object.

A simple call to the close() method will do the job. If you close the Connection object first, it will close the PreparedStatement object as well. However, you should always explicitly close the PreparedStatement object to ensure proper cleanup.

For a better understanding, let us study Prepare - Example Code.

The CallableStatement Objects

Just as a Connection object creates the Statement and PreparedStatement objects, it also creates the CallableStatement object, which would be used to execute a call to a database stored procedure.

Prepared Statement Get Generated Keys Select Free

Creating CallableStatement Object

Suppose, you need to execute the following Oracle stored procedure − Product key generator for games.

NOTE: Above stored procedure has been written for Oracle, but we are working with MySQL database so, let us write same stored procedure for MySQL as follows to create it in EMP database −

Three types of parameters exist: IN, OUT, and INOUT. The PreparedStatement object only uses the IN parameter. The CallableStatement object can use all the three.

Here are the definitions of each −

ParameterDescription
INA parameter whose value is unknown when the SQL statement is created. You bind values to IN parameters with the setXXX() methods.
OUTA parameter whose value is supplied by the SQL statement it returns. You retrieve values from theOUT parameters with the getXXX() methods.
INOUTA parameter that provides both input and output values. You bind variables with the setXXX() methods and retrieve values with the getXXX() methods.

The following code snippet shows how to employ the Connection.prepareCall() method to instantiate a CallableStatement object based on the preceding stored procedure −

The String variable SQL, represents the stored procedure, with parameter placeholders.

Using the CallableStatement objects is much like using the PreparedStatement objects. You must bind values to all the parameters before executing the statement, or you will receive an SQLException.

If you have IN parameters, just follow the same rules and techniques that apply to a PreparedStatement object; use the setXXX() method that corresponds to the Java data type you are binding.

When you use OUT and INOUT parameters you must employ an additional CallableStatement method, registerOutParameter(). The registerOutParameter() method binds the JDBC data type, to the data type that the stored procedure is expected to return.

Once you call your stored procedure, you retrieve the value from the OUT parameter with the appropriate getXXX() method. This method casts the retrieved value of SQL type to a Java data type.

Closing CallableStatement Object

Just as you close other Statement object, for the same reason you should also close the CallableStatement object.

A simple call to the close() method will do the job. If you close the Connection object first, it will close the CallableStatement object as well. However, you should always explicitly close the CallableStatement object to ensure proper cleanup.

Prepared Statement Get Generated Keys Select 1

For a better understanding, I would suggest to study Callable - Example Code.