JDBC for MySQL - Herong's Tutorial Examples - v3.12, by Herong Yang
Creating CallableStatement Objects with INOUT Parameters
This section describes how to create CallableStatement objects with INOUT parameters.
MySQL procedures do support INOUT parameters, which should be handled like IN parameters and OUT parameters as shown in the previous tutorial.
In a previous tutorial, I defined a store procedure called, C2F(), with 2 INOUT parameters. The program below shows you to create a CallableStatement object to execute this stored procedure:
/* MySqlCallInoutParameter.java * Copyright (c) HerongYang.com. All Rights Reserved. */ import java.sql.*; public class MySqlCallInoutParameter { public static void main(String [] args) { Connection con = null; try { com.mysql.cj.jdbc.MysqlDataSource ds = new com.mysql.cj.jdbc.MysqlDataSource(); ds.setServerName("localhost"); ds.setPortNumber(3306); ds.setDatabaseName("HerongDB"); ds.setUser("Herong"); ds.setPassword("TopSecret"); con = ds.getConnection(); // Create CallableStatement CallableStatement cs = con.prepareCall("CALL C2F(?,?)"); // Register INOUT parameters cs.registerOutParameter(1, java.sql.Types.REAL); cs.registerOutParameter(2, java.sql.Types.REAL); // Provide values for INOUT parameters double celsius = 100.0; cs.setDouble(1,celsius); // Execute the CALL statement and ignore result sets cs.executeUpdate(); // Retrieve values from INOUT parameters double fahrenheit = cs.getDouble(2); System.out.println("First test:"); System.out.println(" Celsius = "+celsius); System.out.println(" Fahrenheit = "+fahrenheit); // Second test celsius = 0.0; cs.setDouble(1,celsius); cs.executeUpdate(); fahrenheit = cs.getDouble(2); System.out.println("First test:"); System.out.println(" Celsius = "+celsius); System.out.println(" Fahrenheit = "+fahrenheit); // Close resource cs.close(); con.close(); } catch (Exception e) { System.err.println("Exception: "+e.getMessage()); e.printStackTrace(); } } }
The execution gave me one surprise. The second test failed with an error that I don' understand:
herong> java -cp .:mysql-connector-java.jar \ MySqlCallInoutParameter.java First test: Celsius = 100.0 Fahrenheit = 212.0 Exception: Data truncated for column 'F' at row 1 java.sql.SQLException: Data truncated for column 'F' at row 1 at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:998) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3847) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3783) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2447) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2594) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2545) at com.mysql.jdbc.PreparedStatement.executeInternal(...) at com.mysql.jdbc.PreparedStatement.executeUpdate(...) ... at MySqlCallInoutParameter.main(MySqlCallInoutParameter.java:41)
Table of Contents
JDBC (Java Database Connectivity) Introduction
MySQL JDBC Driver (MySQL Connector/J)
MySQL - Reference Implementation of JdbcRowSet
►MySQL - JBDC CallableStatement
Overview of CallableStatement Objects
"CREATE PROCEDURE" - Creating a Simple Procedure
Creating Procedures with IN and OUT Parameters
Creating Procedures with INOUT Parameters
Creating Procedures with Multiple Queries
Creating CallableStatement Objects with prepareCall()
Capturing ResultSet with executeQuery()
Creating CallableStatement Objects with Parameters
Common Errors with CallableStatement Parameters
►Creating CallableStatement Objects with INOUT Parameters
Retrieving Multiple ResultSet Objects
Executing Stored Procedures without Permission
getProcedures() - Listing Stored Procedures
MySQL CLOB (Character Large Object) - TEXT
MySQL BLOB (Binary Large Object) - BLOB