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Java sql error when trying to update database

I am having a sql syntax issue when I am trying to update my databse through my update method which is trigured by a button
here is the button code
update.addActionListener(e -> {
int i = table.getSelectedRow();
if (i >= 0) {
model.setValueAt(PackId.getText(), i, 0);
model.setValueAt(PackName.getText(), i, 1);
model.setValueAt(VendorName.getText(), i, 2);
model.setValueAt(PackValue.getText(), i, 3);
try {
updatepacks(PackId,PackName,VendorName,PackValue);
} catch (SQLException throwables) {
throwables.printStackTrace();
}
} else {
System.out.println("Update Error");
}
The update method code
public void updatepacks(JTextField PackId, JTextField PackName, JTextField VendorName, JTextField PackValue) throws SQLException {
try{
Connection conn = DriverManager.getConnection("jdbc:sqlite:packsver3.db");
String sqlupdate = "Update packs" + " SET PackName = ?" + " VendorName = ?" + "PackValue = ? " + "Where PackId = ? ";
try (PreparedStatement ps = conn.prepareStatement(sqlupdate)) {
ps.setString(1, String.valueOf(PackId));
ps.setString(2, String.valueOf(PackName));
ps.setString(3, String.valueOf(VendorName));
ps.setString(4, String.valueOf(PackValue));
ps.executeUpdate();
}
} catch (Exception e) {
e.printStackTrace();
}
}
And the error

You missed the commas in the UPDATE statement. It should look like:
String sqlupdate = "Update packs"
+ " SET PackName = ?, " // added comma at the end
+ " VendorName = ?, " // added comma at the end
+ "PackValue = ? "
+ "Where PackId = ? ";

Connecting to different schemas using prepared statement

I have the following code running fine with one sql statement selectEmpShowDocs_SQL referring to schema1. In this scenario, I have hard coded the value of empID as 2 as shown in the sql below :
private String selectEmpShowDocs_SQL =
"SELECT " +
"emp_doc " +
"FROM " +
"schema1.emp_info " +
"WHERE " +
"doc_id = ? "+
"AND"+
"empID = 2";
Now, I have another sql statement which is retrieving the emp_id value and instead of hardcoding the value just like I did above for empID, I want to pass the value of emp_id obtained from the following sql statement to the above sql statement. This is the statement which is referring to schema2.
private String selectEmpIDSQL =
"SELECT " +
"emp_id " +
"FROM " +
"schema2.emp_id " +
"WHERE " +
"company_id = 435 "
I am wondering is it possible to connect with two different schemas with one prepared statement? Here someone mentioned that prepared statement is bound to a specific database and in that case if it's not possible, what would be the best approach for me?
Here is the full code that works fine for me using only the SQL query referring to schema1.
public List<EmployeeDocument> getEmployeeDocument(String docId, Integer employeeID) throws DaoException
{
StopWatch stopWatch = new StopWatch();
stopWatch.start();
DataSource ds = null;
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
List<EmployeeDocument> empShowDocs = new ArrayList<EmployeeDocument>();
try {
ds = jdbcTemplate.getDataSource();
conn = ds.getConnection();
pstmt = conn.prepareStatement(selectEmpShowDocs_SQL);
logger.debug("sql query :" + selectEmpShowDocs_SQL);
System.out.println(selectEmpShowDocs_SQL);
pstmt.setString(1, docId);
logger.debug("sql parameters, docId:" + docId);
rs = pstmt.executeQuery();
while(rs.next()) {
EmployeeDocument empShowDocRecord = new EmployeeDocument();
empShowDocRecord.setEmp_Content(rs.getString("emp_doc")));
empShowDocs.add(empShowDocRecord);
}
} catch(Throwable th) {
throw new DaoException(th.getMessage(), th);
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
rs = null;
}
if (pstmt != null) {
try {
pstmt.close();
} catch(SQLException sqe) {
sqe.printStackTrace();
}
pstmt = null;
}
if (conn != null) {
try {
conn.close();
} catch (SQLException sqle) {
sqle.printStackTrace();
}
conn = null;
}
if (ds != null) {
ds = null;
}
}
return empShowDocs;
}
private String selectEmpShowDocs_SQL =
"SELECT " +
"emp_doc " +
"FROM " +
"schema1.emp_info " +
"WHERE " +
"doc_id = ? "+
"AND"+
"empID = 2";
private String selectEmpIDSQL =
"SELECT " +
"emp_id " +
"FROM " +
"schema2.emp_id " +
"WHERE " +
"company_id = 435 "

Error access to database

Please explain to me differents between
private boolean inUse(JDBCTemplates jdbc, BigInteger firmwareId) {
String query = "select * from references ref " +
"where ref.attr_id = 9 " +
"and ref.reference = ?";
try {
s = (String) jdbc.selectForObject(query....);
} catch (Exception e) {
log.info(e.toString());
}
return ...;
}
and
private boolean inUse(JDBCTemplates jdbc, BigInteger firmwareId) {
String query = "select * from references ref " +
"where ref.attr_id = 9 " +
"and ref.reference =" + firmwareId;
try {
s = (String) jdbc.selectForObject(query....);
} catch (Exception e) {
log.info(e.toString());
}
return ...;
}
In the second case, I get an access error to the database (jdbc.DataAccessException: Error due to access to database), and in the first case everything works.

try to modify your code this way, pay attention to the string query and the parameter:
private boolean inUse(JDBCTemplates jdbc, BigInteger firmwareId) {
String query = "select * from references ref " +
"where ref.attr_id = 9 " +
"and ref.reference ='" + firmwareId+"'";//Here might be the error
try {
s = (String) jdbc.selectForObject(query....);
} catch (Exception e) {
log.info(e.toString());
}
return ...;
}
try this and let us know if it works or not, so that we can try something else

SQL query not executing in java

Im trying to execute a query through a java program but it doesn't execute. here's the method
public List<Usuario> darProveedores() throws Exception{
PreparedStatement st=null;
ArrayList<Usuario> respuesta = new ArrayList<Usuario>();
String consulta ="SELECT u.direccion_electronica AS dirE, "
+ "u.login AS login, "
+ "u.palabra_clave AS clave, "
+ "u.rol AS rol, "
+ "u.tipo_persona AS tipoPer, "
+ "u.documento_identificacion AS docID, "
+ "u.nombre AS nombre, "
+ "u.nacionalidad AS naci, "
+ "u.direccion_fisica AS dirF, "
+ "u.telefono AS tel, "
+ "u.ciudad AS ciudad, "
+ "u.departamento AS depto, "
+ "u.codigo_postal AS codPostal "
+ " FROM usuarios u "
+ " WHERE u.rol='Proveedor' ";
try{
iniTemp();
establecerConexion(cadenaConexion, usuario, clave);
st = conexion.prepareStatement(consulta);
ResultSet r= st.executeQuery(consulta);
while(r.next()){
String dirE= r.getString("dirE");
String login = r.getString("login");
String clave = r.getString("clave");
String rol = r.getString("rol");
String tipoPer = r.getString("tipoPer");
String docID = r.getString("docID");
String nombre = r.getString("nombre");
String naci = r.getString("naci");
String dirF = r.getString("dirF");
String tel= r.getString("tel");
String ciudad = r.getString("ciudad");
String depto = r.getString("depto");
String codPostal = r.getString("codPostal");
Usuario u = new Usuario(login, dirE, clave, rol, tipoPer, Integer.parseInt(docID), nombre, naci, dirF, Integer.parseInt(tel), ciudad, depto, Integer.parseInt(codPostal));
respuesta.add(u);
}
}
catch(Exception e)
{
e.printStackTrace();
}
finally{
if (st != null)
{
try {
st.close();
} catch (SQLException exception) {
throw new Exception("ERROR: ConsultaDAO: loadRow() = cerrando una conexion.");
}
}
closeConnection(conexion);
}
return respuesta;
}
I have executed the query on SQL Developer and it returns a table with values, but when
i do it through here the while(r.next()) instruction says there are no rows in the answer

You don't need to use a PreparedStatement when there are no parameters. Just use Statement in place of PreparedStatement, and st = conexion.createStatement() to create it.

Getting SQL error 1078 Before start of result set in Java program [duplicate]

This question already has answers here:
ResultSet exception - before start of result set
(6 answers)
Closed 5 years ago.
I have a Java method that is supposed to get column values from one MySQL row and create a string with the values. When run, it generates a SQL error 1078 "Before start of result set."
Here is the the class in which the error is occuring (Problem is in listPosesInSection method:
/** Class used to access the database */
import java.sql.*;
import java.util.ArrayList;
import javax.swing.JOptionPane;
public class YogaDatabaseAccess {
String dbUrl = "jdbc:mysql://localhost/yoga";
private Connection connection;
private ResultSet rset;
private ResultSetMetaData rsMetaData;
private Statement statement;
private PreparedStatement pStatementAll = null;
private PreparedStatement pStatementPartial = null;
// Strings for queries and updates
String strListPosesNotPrimary;
String strInsertNewClass;
String strInsertNewSection;
String strInsertNewPose;
String strUpdateClass;
String strUpdateSection;
String strUpdatePose;
String strArrangePoseOrder;
private String[] poseArray;
// Constructor
YogaDatabaseAccess() {
connectToDatabase();
}
// Method that connects to database
private void connectToDatabase() {
try {
connection = DriverManager.getConnection(dbUrl, "Kyle", "Kullerstrand#2");
System.out.println("Database connected");
}
catch(SQLException e) {
System.out.println(e.getMessage());
}
}
// Query that returns lists to be used with combo boxes
public String listForBoxes(String listName) {
// List to be returned
String strList = "";
// Determine name of the database table for this list
String listTableName;
if (listName == "pose")
listTableName = listName + "s";
else if (listName == "class")
listTableName = listName + "es";
else
listTableName = listName;
// Determine the database column name for this list
String listColumnName = listName + "_name";
// Run the query
try {
statement = connection.createStatement();
rset = statement.executeQuery("SELECT DISTINCT " + listColumnName + " FROM " + listTableName +
" ORDER BY " + listColumnName);
while (rset.next()){
strList = strList + rset.getString(listColumnName) + ", ";
}
} catch (SQLException e) {
e.printStackTrace();
}
return strList;
}
// Query that returns list of primary poses for a section
public String listPrimaryPoses(String sectionName) {
// List to be returned
String strList = "";
// Run the query
try {
statement = connection.createStatement();
rset = statement.executeQuery("SELECT DISTINCT pose_name FROM poses WHERE primarily_suitable_for = '" + sectionName +
"' OR primarily_suitable_for = 'Anything' ORDER BY pose_name");
while (rset.next()){
strList = strList + rset.getString("pose_name") + ", ";
}
} catch (SQLException e) {
e.printStackTrace();
}
return strList;
}
// Query that returns list of secondary poses for a section
public String listSecondaryPoses(String sectionName) {
// List to be returned
String strList = "";
// Run the query
try {
statement = connection.createStatement();
rset = statement.executeQuery("SELECT DISTINCT pose_name FROM poses WHERE sometimes_suitable_for = '" + sectionName + "' ORDER BY pose_name");
while (rset.next()){
strList = strList + rset.getString("pose_name") + ", ";
}
} catch (SQLException e) {
e.printStackTrace();
}
return strList;
}
// Query that returns the poses within a specific section
public String listPosesInSection(String tableName, String sectionName) {
String strList;
StringBuilder strBuilderList = new StringBuilder("");
// Run the query
try {
statement = connection.createStatement();
// Query will collect all columns from one specific row
rset = statement.executeQuery("SELECT * FROM " + tableName + " WHERE " + tableName + "_name = '" + sectionName + "'");
while (rset.next()) {
for (int i = 2; i <= countColumnsInTable(tableName); i++) // First value (0) is always null, skip section name (1)
if (rset.getString(i) != null) // If column has a value
strBuilderList.append(rset.getString(i) + "\n");
}
} catch (SQLException e) {
e.printStackTrace();
}
strList = strBuilderList.toString();
return strList.replaceAll(", $",""); // Strips off the trailing comma
}
// Insert statement that inserts a new class into the classes table
public void insertNewClass(String className) {
/** String insert = "INSERT INTO poses (pose_name, primarily_suitable_for, sometimes_suitable_for) values(?, ?, ?)";
System.out.println("About to create the prepared statement");
// Run the insert
try {
pStatement = connection.prepareStatement(insert);
// statement.execute("INSERT IGNORE INTO poses VALUES ('" + poseName + "', '" + suitableFor + "', '" + suitableForSometimes + "')");
pStatement.setString(1, poseName);
pStatement.setString(2, suitableFor);
pStatement.setString(3, suitableForSometimes);
System.out.println("Created the prepared statement");
// execute query, and return number of rows created
pStatement.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
} */
}
// Insert statement that inserts a new pose into poses table
public void insertNewPose(String poseName, String suitableFor, String suitableForSometimes) {
String insertAll = "INSERT INTO poses (pose_name, primarily_suitable_for, sometimes_suitable_for) values(?, ?, ?)";
String insertPartial = "INSERT INTO poses (pose_name, primarily_suitable_for) values(?, ?)";
// Run the insert
try {
if (suitableForSometimes == "NULL") { // Insert statement contains a null value for sometimes suitable column
pStatementPartial = connection.prepareStatement(insertPartial);
pStatementPartial.setString(1, poseName);
pStatementPartial.setString(2, suitableFor);
pStatementPartial.executeUpdate();
} else { // Insert statement contains values for all three columns
pStatementAll = connection.prepareStatement(insertAll);
pStatementAll.setString(1, poseName);
pStatementAll.setString(2, suitableFor);
pStatementAll.setString(3, suitableForSometimes);
pStatementAll.executeUpdate();
}
} catch (SQLException e) {
System.err.println("SQLException: " + e.getMessage() + ":" + e.getSQLState());
JOptionPane.showMessageDialog(null, "This pose already exists.");
} finally {
SQLWarning w;
try {
for (w = connection.getWarnings(); w != null; w = w.getNextWarning())
System.err.println("WARNING: " + w.getMessage() + ":" + w.getSQLState());
} catch (SQLException e) {
e.printStackTrace();
JOptionPane.showMessageDialog(null, "An unknown error in the yoga design program has occurred.");
}
}
}
// Insert statement that inserts a new section into warmup, work or restore sections
public void insertNewSection(String sectionType, String sectionName, ArrayList<String> poses) {
System.out.println("insertNewSection method was called");
int maxColumns = countColumnsInTable(sectionType);
poseArray = new String[poses.size()];
poseArray = poses.toArray(poseArray);
if (poseArray.length == 0)
JOptionPane.showMessageDialog(null, "There are no poses in this section. Please add poses.");
// Create a list of columns of the table for the INSERT statement
StringBuilder columns = new StringBuilder(sectionType + "_name");
for (int c = 1; c < maxColumns; c++)
columns.append(", pose_" + c);
// Create a string list of poses, separated by commas, from the array
StringBuilder values = new StringBuilder();
values.append("'" + poseArray[0] + "'");
for (int v = 1; v < poseArray.length - 1; v++)
values.append(", '" + poseArray[v] + "'");
// make sure query uses correct number of columns by padding the query with NULL
for (int i = poseArray.length; i < maxColumns; i++)
values.append(", NULL");
String posesToAddToSection = values.toString();
// The string containing the entire insert statement
String insert = "INSERT INTO " + sectionType + " (" + columns + ") VALUES ('" + sectionName + "', " + posesToAddToSection + ")";
// Run the insert
try {
statement = connection.createStatement();
statement.executeUpdate(insert);
} catch (SQLException e) {
System.err.println("SQLException: " + e.getMessage() + ":" + e.getSQLState());
JOptionPane.showMessageDialog(null, "An error in the yoga design program has occurred. SQLException: " +
e.getMessage() + ":" + e.getSQLState());
} finally {
SQLWarning w;
try {
for (w = connection.getWarnings(); w != null; w = w.getNextWarning())
System.err.println("WARNING: " + w.getMessage() + ":" + w.getSQLState());
} catch (SQLException e) {
e.printStackTrace();
JOptionPane.showMessageDialog(null, "An unknown error in the yoga design program has occurred.");
}
}
}
// Statement that deletes rows from tables
public void deleteRow(String tableName, String columnName, String rowName) {
String delete = "DELETE FROM " + tableName + " WHERE " + columnName + " = '" + rowName + "'";
// Run the insert
try {
statement = connection.createStatement();
statement.executeUpdate(delete);
System.out.println("Delete statement was run on Java's end.");
} catch (SQLException e) {
System.err.println("SQLException: " + e.getMessage() + ":" + e.getSQLState());
JOptionPane.showMessageDialog(null, "Sorry, something went wrong: SQLException: " +
e.getMessage() + ":" + e.getSQLState());
} finally {
SQLWarning w;
try {
for (w = connection.getWarnings(); w != null; w = w.getNextWarning())
System.err.println("WARNING: " + w.getMessage() + ":" + w.getSQLState());
} catch (SQLException e) {
e.printStackTrace();
}
}
}
// Method for getting the number of columns in a table using metadata
public int countColumnsInTable(String sectionType) {
int count = 16;
try {
// System.out.println(sectionType);
statement = connection.createStatement();
rset = statement.executeQuery("SELECT * FROM " + sectionType);
rsMetaData = rset.getMetaData();
count = rsMetaData.getColumnCount();
// System.out.println("Column count is " + count);
} catch (SQLException e) {
e.printStackTrace();
}
return count;
}
// Close the database and release resources
public void closeDatabase() {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
And here is the beginning of the error list:
java.sql.SQLException: Before start of result set
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1078)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:920)
at com.mysql.jdbc.ResultSetImpl.checkRowPos(ResultSetImpl.java:855)
at com.mysql.jdbc.ResultSetImpl.getStringInternal(ResultSetImpl.java:5773)
at com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5693)
at YogaDatabaseAccess.listPosesInSection(YogaDatabaseAccess.java:125)
at YogaSectionDesigner$5.actionPerformed(YogaSectionDesigner.java:229)

May be you can check this out:
ResultSet exception - before start of result set
Had the same Problem. Solved it that way.