sql jdbc getgeneratedkeys returns column "id" not found, column type unknown

Question

I want to retrieve the most recently updated value in the table using an insert query.

these are the datatypes in my sql table.

int(11) // primary key auto increment, not being assigned by sqlQuery

varchar(30)

timestamp  // has a default value. but i am explicit assigning it using CURRENT_TIMESTAMP

varchar(300)

varchar(300)

varchar(300)

int(11)

varchar(300)


        // java code
        statement.executeUpdate(sqlQuery, Statement.RETURN_GENERATED_KEYS);
        ResultSet rs = statement.getGeneratedKeys();
        System.out.println("here: " + rs.getMetaData().getColumnCount());
        System.out.println("here1: " + rs.getMetaData().getColumnName(1));
        // none of the following 3 works
        System.out.println("id: " + rs.getInt(1));
        System.out.println("id: " + rs.getInt("GENERATED_KEY"));
        System.out.println("id: " + rs.getInt("id"));

for a bit of background see this

rs.getMetaData().getColumnTypeName(1) tells me column type UNKNOWN

stack trace SEVERE: null java.sql.SQLException at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.ResultSetImpl.checkRowPos(ResultSetImpl.java:815) at com.mysql.jdbc.ResultSetImpl.getStringInternal(ResultSetImpl.java:5528) at com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5448)

Answer 1

You need to call rs.next():

int autoIncKeyFromApi = -1;
rs = stmt.getGeneratedKeys();
if (rs.next()) {
    autoIncKeyFromApi = rs.getInt(1);
} else {
    // do what you have to do
}
System.out.println(autoIncKeyFromApi);