Mysql/JDBC update query problem

[thelinuxguy]

Hi

I am trying to make an update query for java jdbc/mysql.
The query runs as follows:-
result = statement.executeUpdate("update account set balance = balance - " + amountToWithdraw +
" where account.account_number = '" + accountNumber + "'" + "and account.sortcode = " + "'"+sortCode+"'");

I keep getting the error message:-
Account.java:126: incompatible types
found : int
required: java.sql.ResultSet

result = statement.executeUpdate("update account set balance = balance - " + amountToWithdraw +
^
1 error

I know that the syntax is correct because I have it working in mysql, I dont quite know what this means.

Any help would be appreciated

theLinuxGuy

[thelinuxguy]

Hi

I have corrected the mistake - the problem was I had adjusted a select query that had used a result set with the statement connection, but when executing an update there is no such result set, nothing is returned from the query so there is no result set.

I corrected the query by simply adding the line statement = connection.createStatement(); and removed the previous line statement = connection.createStatement(//resultSetdetails);.

as follows if it helps anybody ever!

public int makeWithdrawel(int amountToWithdrawIn)
{
amountToWithdraw = amountToWithdrawIn;
try
{
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/atm";
Connection connection = DriverManager.getConnection(
url, "user", "password");
statement = connection.createStatement();
statement.executeUpdate("update account set balance = balance - " + amountToWithdraw +
" where account.account_number = '" + accountNumber + "'");

connection.close();

}

[Steve11235]

Just an off-topic suggestion. Look into using PreparedStatement. It seems like a pain in the aft, but CreateStatement is *very*, as in noticeable, slow. You can reuse prepared statements, they are easier to write and debug, and the stop SQL injection attacks.

[thelinuxguy]

Hi Steve11235

Thanks for the suggestion, Ill look into prepared statements.

Kind regards

theLinuxGuy