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Inserting issue into the database via java

I have a bit of a problem with inserting some data in the database. The data is being read by an CSV parser and changed to data besides that, I continue to get this error message:
Connected to the PostgreSQL server successfully.
Naam van de garage: P_Erasmusbrug, Longditude: 4.482313155, Latitude: 51.91024645
org.postgresql.util.PSQLException: The column index is out of range: 1, number of columns: 0.
at org.postgresql.core.v3.SimpleParameterList.bind(SimpleParameterList.java:65)
at org.postgresql.core.v3.SimpleParameterList.setStringParameter(SimpleParameterList.java:128)
at org.postgresql.jdbc.PgPreparedStatement.bindString(PgPreparedStatement.java:1023)
at org.postgresql.jdbc.PgPreparedStatement.setString(PgPreparedStatement.java:374)
at org.postgresql.jdbc.PgPreparedStatement.setString(PgPreparedStatement.java:358)
at Database.ConnectDatabase.parser(ConnectDatabase.java:80)
at Events.CSVReader.main(CSVReader.java:40)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Thank you for your service.
Naam van de garage: P_St.Jacobsplaats, Longditude: 4.482054381, Latitude: 51.92410235
Thank you for your service.
Naam van de garage: P_Schouwburgplein, Longditude: 4.473618335, Latitude: 51.92102728
org.postgresql.util.PSQLException: The column index is out of range: 1, number of columns: 0.
Which continues for all the other lines of data. Is there maybe a way to fix this as I don't really understand what the error message includes..
The a, b2, and c2 are variables for the ''name'' , ''londitude'' and ''latitude''.
package Database;
import java.io.*;
import java.sql.*;
import java.util.HashMap;
import java.sql.SQLException;
public class ConnectDatabase {
private final String url = "jdbc:postgresql://localhost/Project3";
private final String user = "postgres";
private final String password = "kaas123";
private Connection conn;
public Connection connect() {
Connection conn = null;
try {
conn = DriverManager.getConnection(url, user, password);
System.out.println("Connected to the PostgreSQL server successfully.");
} catch (SQLException exception) {
System.out.println(exception.getMessage());
}
this.conn = conn;
return conn;
}
public HashMap getGarages() {
HashMap<String, Double> newHashMap = new HashMap<String, Double>();
try {
Statement stmt = conn.createStatement();
ResultSet rs;
rs = stmt.executeQuery("SELECT deelgemeente, COUNT(garagenaam) FROM garages GROUP BY deelgemeente");
while (rs.next()) {
String deelGemeenteNaam = rs.getString("deelgemeente");
double garageNaamCount = rs.getDouble("COUNT");
newHashMap.put(deelGemeenteNaam, garageNaamCount);
}
} catch (Exception e) {
System.err.println("Got an exception!");
System.err.println(e.getMessage());
}
return newHashMap;
}
public HashMap getTheftYear(int year) {
HashMap<String, Double> newHashMap = new HashMap<String, Double>();
try {
Statement stmt = conn.createStatement();
ResultSet rs;
rs = stmt.executeQuery("SELECT deelgemeente, percentagediefstal FROM autodiefstal WHERE jaar = " + year);
while (rs.next()) {
String deelGemeenteNaam = rs.getString("deelgemeente");
double deelPercentage = rs.getDouble("percentagediefstal");
newHashMap.put(deelGemeenteNaam, deelPercentage);
}
} catch (Exception e) {
System.err.println("Got an exception!");
System.err.println(e.getMessage());
}
return newHashMap;
}
public int parser(String a, float b2, float c2) {
int updated = 0;
Connection conn = null;
PreparedStatement stmt = null;
try {
conn = DriverManager.getConnection(url, user, password);
String insertSQL = "INSERT INTO testparser(garagenaam, xpos, ypos) VALUES(" + a + "," + b2 + "," + c2 + ")";
stmt = conn.prepareStatement(insertSQL);
stmt.setString(1, a);
stmt.setFloat(2, b2);
stmt.setFloat(3, c2);
System.out.println("Inserted data into the database...");
updated = stmt.executeUpdate();
} catch (SQLException se) {
se.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (stmt != null)
conn.close();
} catch (SQLException se) {
}
try {
if (conn != null)
conn.close();
} catch (SQLException se) {
se.printStackTrace();
}
}
System.out.println("Thank you for your service.");
this.conn = conn;
return updated;
}
}

You aren't correctly using the ? placeholders system, replace :
String insertSQL = "INSERT INTO testparser(garagenaam, xpos, ypos) VALUES(" + a + "," + b2 + "," + c2 + ")";
with
String insertSQL = "INSERT INTO testparser(garagenaam, xpos, ypos) VALUES(?,?,?)";

How to start Derby server on the specified port by java

I tried to test Derby sample source code. Unfortunately it failed: Cannot connect Derby database: connection refused
I was told that I haven't started a server. Official tutorial:
Doesn't start any server.I have no feedback after C:\Apache\db-derby-10.4.1.3-bin\lib> java -jar derbyrun.jar server start just empty line shows and the derbyrun.jar ends.
Doesn't show how to create server on the specified port
My question is: How to start a server on the specified port so the posted code works:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSetMetaData;
public class Restaurants
{
private static String dbURL = "jdbc:derby://localhost:1526/myDB;create=true;user=me;password=mine";
private static String tableName = "restaurants";
// jdbc Connection
private static Connection conn = null;
private static Statement stmt = null;
public static void main(String[] args)
{
createConnection();
insertRestaurants(5, "LaVals", "Berkeley");
selectRestaurants();
shutdown();
}
private static void createConnection()
{
try
{
Class.forName("org.apache.derby.jdbc.ClientDriver").newInstance();
//Get a connection
conn = DriverManager.getConnection(dbURL);
}
catch (Exception except)
{
except.printStackTrace();
}
}
private static void insertRestaurants(int id, String restName, String cityName)
{
try
{
stmt = conn.createStatement();
stmt.execute("insert into " + tableName + " values (" +
id + ",'" + restName + "','" + cityName +"')");
stmt.close();
}
catch (SQLException sqlExcept)
{
sqlExcept.printStackTrace();
}
}
private static void selectRestaurants()
{
try
{
stmt = conn.createStatement();
ResultSet results = stmt.executeQuery("select * from " + tableName);
ResultSetMetaData rsmd = results.getMetaData();
int numberCols = rsmd.getColumnCount();
for (int i=1; i<=numberCols; i++)
{
//print Column Names
System.out.print(rsmd.getColumnLabel(i)+"\t\t");
}
System.out.println("\n-------------------------------------------------");
while(results.next())
{
int id = results.getInt(1);
String restName = results.getString(2);
String cityName = results.getString(3);
System.out.println(id + "\t\t" + restName + "\t\t" + cityName);
}
results.close();
stmt.close();
}
catch (SQLException sqlExcept)
{
sqlExcept.printStackTrace();
}
}
private static void shutdown()
{
try
{
if (stmt != null)
{
stmt.close();
}
if (conn != null)
{
DriverManager.getConnection(dbURL + ";shutdown=true");
conn.close();
}
}
catch (SQLException sqlExcept)
{
}
}
}

Setting port numbers
By default, Derby using the Network Server listens on TCP/IP port number 1527. If you want to use a different port number, you can specify it on the command line when starting the Network Server. For example:
java org.apache.derby.drda.NetworkServerControl start -p 1088
However, it is better to specify the port numbers by using any of the following methods
1. Change the startNetworkServer.bat or startNetworkServer.ksh scripts
2. Use the derby.drda.portNumber property in derby.properties
Please refer to:
https://db.apache.org/derby/docs/10.5/adminguide/tadminappssettingportnumbers.html

JDBC mysql does not support placeholder of LIMIT in PreparedStatement?

I used mysql-connector-java-5.1.38 to operate mysql-community-5.7.10.0 on Windows 10 64-bit.
I try to bind value in limit for pagination
"SELECT * FROM employee LIMIT ?, ?"
However the result shows:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '?, ?' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
at com.mysql.jdbc.Util.getInstance(Util.java:387)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:939)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3878)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3814)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2478)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2625)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2547)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2505)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1370)
at SqlTest.main(SqlTest.java:65)
However, I tried sql in navicat directly but could get the correct answer:
INSERT INTO employee VALUES (1, 'Zara');
INSERT INTO employee VALUES (2, 'Zara');
INSERT INTO employee VALUES (3, 'Zara');
INSERT INTO employee VALUES (4, 'Zara');
SET #skip=1; SET #numrows=5;
PREPARE STMT FROM 'SELECT * FROM employee LIMIT ?, ?';
EXECUTE STMT USING #skip, #numrows;
Here is my entire code:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class SqlTest {
// JDBC driver name and database URL
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost:3306/employee?useServerPrepStmts=false";
// Database credentials
static final String USER = "root";
static final String PASS = "whaty123";
static final int PAGESIZE = 10;
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
PreparedStatement pStmt = null;
// STEP 2: Register JDBC driver
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
// STEP 3: Open a connection
System.out.println("Connecting to database...");
try {
conn = DriverManager.getConnection(DB_URL, USER, PASS);
} catch (SQLException e) {
e.printStackTrace();
}
String insertPreparedSql = "INSERT INTO employee " + "VALUES (?, 'Zara')";
try {
pStmt = conn.prepareStatement(insertPreparedSql);
} catch (SQLException e) {
e.printStackTrace();
}
for (int i = 0; i < 100; i++) {
try {
pStmt.setInt(1, i);
pStmt.execute();
} catch (SQLException e) {
e.printStackTrace();
}
}
String selectLimitSql = "SELECT * FROM employee LIMIT ?, ?";
// select with limit
try {
pStmt = conn.prepareStatement(selectLimitSql);
pStmt.setFetchSize(PAGESIZE);
pStmt.setMaxRows(PAGESIZE);
pStmt.setFetchDirection(ResultSet.FETCH_FORWARD);
int pageNo = 0;
pStmt.setInt(1, pageNo * PAGESIZE);
pStmt.setInt(2, PAGESIZE);
ResultSet rs = pStmt.executeQuery(selectLimitSql);
while (!rs.wasNull()) {
while(rs.next()) {
System.out.println("id: " + String.valueOf(rs.getInt(1)) + " name: " + rs.getString(2));
}
pageNo = pageNo + 1;
pStmt.setInt(1, pageNo * PAGESIZE);
pStmt.setInt(2, PAGESIZE);
pStmt.executeQuery(selectLimitSql);
}
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

Your problem is not about the syntax or MySQL support for LIMIT since it's supported. The problem is about the way you are executing the PreparedStatement.
When using PreparedStatement you may not use the executeQuery(String sql), because you've prepared the SQL string formerly for the execution, and no need to pass it again in the executeQuery() method. So do this
ResultSet rs = pStmt.executeQuery();
instead of
ResultSet rs = pStmt.executeQuery(selectLimitSql);
With passing again the selectLimitSql (like above line), you are ignoring the following lines:
pStmt.setInt(1, pageNo * PAGESIZE);
pStmt.setInt(2, PAGESIZE);
and it is like executing your primitive pure sql which contains '?, ?' place holders and you get that exception.

You do not need to pass the query string. Do this
ResultSet rs = pStmt.executeQuery();
instead of
ResultSet rs = pStmt.executeQuery(selectLimitSql);
Also, remove the following lines as pagination is taken care of limit in query itself.
pStmt.setFetchSize(PAGESIZE);
pStmt.setMaxRows(PAGESIZE);
pStmt.setFetchDirection(ResultSet.FETCH_FORWARD);
Following code works:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class SqlTest {
// JDBC driver name and database URL
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost:3306/company?useServerPrepStmts=false";
// Database credentials
static final String USER = "root";
static final String PASS = "rohan";
static final int PAGESIZE = 10;
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
PreparedStatement pStmt = null;
// STEP 2: Register JDBC driver
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
// STEP 3: Open a connection
System.out.println("Connecting to database...");
try {
conn = DriverManager.getConnection(DB_URL, USER, PASS);
} catch (SQLException e) {
e.printStackTrace();
}
String insertPreparedSql = "INSERT INTO employee " + "VALUES (?, 'Zara', 'Zara','Zara')";
try {
pStmt = conn.prepareStatement(insertPreparedSql);
} catch (SQLException e) {
e.printStackTrace();
}
for (int i = 0; i < 100; i++) {
try {
pStmt.setInt(1, i*10);
pStmt.execute();
} catch (SQLException e) {
e.printStackTrace();
}
}
String selectLimitSql = "SELECT * FROM employee limit ?, ?";
// select with limit
try {
pStmt = conn.prepareStatement(selectLimitSql);
int pageNo = 0;
pStmt.setInt(1, pageNo * PAGESIZE);
pStmt.setInt(2, PAGESIZE);
ResultSet rs = pStmt.executeQuery();
while (!rs.wasNull()) {
while(rs.next()) {
System.out.println("id: " + String.valueOf(rs.getInt(1)) + " name: " + rs.getString(2));
}
pageNo = pageNo + 1;
pStmt.setInt(1, pageNo * PAGESIZE);
pStmt.setInt(2, PAGESIZE);
rs = pStmt.executeQuery();
}
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

USER defined java class step in pentaho data integration

Hi,
I am using the below code in USER DEFINED JAVA CLASS:
//STEP 1. Import required packages import java.sql.*;
import org.pentaho.di.core.database.*;
public class JDBCExample {
// JDBC driver name and database URL
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL ="jdbc:mysql://localhost:1111/mysql";
// Database credentials
static final String USER = "USER";
static final String PASS = "PASS";
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null; try{
//STEP 2: Register JDBC driver
Class.forName("com.mysql.jdbc.Driver");
//STEP 3: Open a connection
System.out.println("Connecting to a selected database...");
conn = DriverManager.getConnection(DB_URL, USER, PASS);
System.out.println("Connected database successfully...");
//STEP 4: Execute a query
System.out.println("Creating statement...");
stmt = conn.createStatement();
String sql = "select id,sorname,src_databasetype,src_databasename from table";
ResultSet rs = stmt.executeQuery(sql);
//STEP 5: Extract data from result set
while(rs.next()){
//Retrieve by column name
int id = rs.getInt("id");
String sorname = rs.getString("sorname");
String src_databasetype = rs.getString("src_databasetype");
String src_databasename = rs.getString("src_databasename");
//Display values
System.out.print("ID: " + id);
System.out.print(", sorname: " + sorname);
System.out.print(", src_databasetype: " + src_databasetype);
System.out.println(", src_databasename: " + src_databasename);
}
rs.close(); }catch(SQLException se){
//Handle errors for JDBC
se.printStackTrace(); }catch(Exception e){
//Handle errors for Class.forName
e.printStackTrace(); }finally{
//finally block used to close resources
try{
if(stmt!=null)
conn.close();
}catch(SQLException se){
}// do nothing
try{
if(conn!=null)
conn.close();
}catch(SQLException se){
se.printStackTrace();
}//end finally try }//end try System.out.println("Goodbye!"); }//end main }//end JDBCExample
Running the code through command prompt its working fine
BUT on running the step(In PDI) alone I am getting error:
Non-abstract class "Processor" must implement method "boolean org.pentaho.di.trans.steps.userdefinedjavaclass.TransformClassBase.processRow(org.pentaho.di.trans.step.StepMetaInterface,
org.pentaho.di.trans.step.StepDataInterface) throws
org.pentaho.di.core.exception.KettleException"

For UDJC, I think instead of putting code in the main method, you need to put it in processRow().
Instead of using -
public static void main(String[] args)
use -
public boolean processRow(StepMetaInterface smi, StepDataInterface sdi) throws KettleException
I am still skeptical if its still going to work as I don't understand what you're trying to do with that code.

Try writing your code in processRow method as follows:
public boolean processRow(StepMetaInterface smi, StepDataInterface sdi) throws KettleException{
Object[] r = getRow();
if (r == null) {
setOutputDone();
return false;
}
Object[] outputRow = createOutputRow(r, data.outputRowMeta.size());
//String row = getString(r)+",";
//setValue(outputRow, row)
putRow(data.outputRowMeta, outputRow);
return true;
}

Display rows in database using java

I was trying to display the rows in the database using Java. My idea is to sort the rows in the database and display them in 3 columns and infinite rows. This is what I have. When I run it, I couldn't see any output. Where did I go wrong?
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.sql.SQLException;
public class Rows {
public static void main(String[] args) throws SQLException,ClassNotFoundException
{
Connection connection = null;
try {
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/testapp";
String user = "root";
String password = "root";
connection = DriverManager.getConnection(url, user, password);
Statement stmt = connection.createStatement();
String sql = "select * from site order by fname;";
stmt.execute(sql);
} catch (ClassNotFoundException e) {
System.err.println("Could not load database driver!");
} catch (SQLException e) {
e.printStackTrace();
}
finally
{
if (connection != null)
{
connection.close();
}
}
}
}
The database table I have is
datas(id int, fname varchar(20)

Statement stmt = connection.createStatement();
String sql = "select id, fname from site order by fname;";
ResultSet rs=stmt.executeQuery(sql);
while(rs.next()){
int id=rs.getInt("id");
.............
}
Reference: Retrieving and Modifying Values from Result Sets

The code should obtain a ResultsSet and iterate through it.
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/testapp";
String user = "root";
String password = "root";
connection = DriverManager.getConnection(url, user, password);
Statement stmt = connection.createStatement();
//You shouldn't need the semi-colon at the end
String sql = "select * from site order by fname;";
//missing piece
ResultSet rs = stmt.executeQuery(sql);
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
System.out.println(id + "\t" + name);
}