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Can't Update the SQL through Java

I'm trying to make CRUD (Create, Read, Update, Delete) to my projects. But it seems the "update" doesn't work. It keeps saying
java.sql.SQLSyntaxErrorException : You have an error in your SQL syntax; check the manual that coresponds to your MariaDB server version for the right syntax to use near "Number" = 0813874810 WHERE Name = "Gregory" at line 1)
What the solution for this?
Here is my code:
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/employeedata", "root", "");
String sql = "UPDATE employeetab SET Name = '" + txtEmployeeName.getText()
+ "',Address = '" + txtEmployeeAddress.getText()
+ "',Gender = '" + gender_type
+ "',Phone Number = '" + txtEmployeePhone.getText()
+ "' WHERE Name = '" + txtEmployeeName.getText() + "'";
stm = conn.prepareStatement(sql);
stm.execute(sql);
JOptionPane.showMessageDialog(this, "Update successfully");
this.setVisible(false);

Problem comes from the space in column Phone Number. To make it work you need to escape the column name with `.
UPDATE employeetab
SET Name = 'something',Address = 'some address',Gender = 'whatever',`Phone Number` = '000000000'
WHERE Name = 'something';
You should follow sql naming conventions, normally words in column names are separated by _. Your column name should be - phone_number.
Also, as mentioned in comments, you should not just add user input into sql queries, because you are leaving yourself wide open for sql injection.

You need to follow the naming conventions , their is space between 'Phone Number' column you should not write like this you need to add _ in between of this two.

try this :
String gender_type = null;
if (ButtonM.isSelected()){
gender_type = "Male";
}else if(ButtonFM.isSelected()){
gender_type = "Female";
}
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/employeedata","root","");
String sql = "UPDATE employeetab SET Name = ? ," +
" Address = ? ," +
" Gender = ? ," +
" Phone Number = ? ," +
" WHERE Name = ? ," ;
PreparedStatement pStmt = conn.prepareCall(sql);
pStmt.setString(1, txtEmployeeName.getText()+"");
pStmt.setString(2, txtEmployeeAddress.getText()+"");
pStmt.setString(3, gender_type+"");
pStmt.setString(4, txtEmployeePhone.getText()+"");
pStmt.setString(5, txtEmployeeName.getText());
pStmt.executeUpdate();
JOptionPane.showMessageDialog(this, "Update successfully");
this.setVisible(false);
}catch (Exception e){
JOptionPane.showMessageDialog(null, e);
}
its cleaner and should work.

Error when updating MySQL database using UPDATE - SET - WHERE method in Eclipse

I am making a program using Eclipse that allows the user to update the volume of chemicals everytime they’re restocked/used, which requires them to enter the ID of the chemical and the amount they would like to add/subtract. A query is then performed to search for the chemical's ID in the database, and its volume is updated accordingly.
However, I’m having difficulties getting the volume to update. I tried adapting MySQL’s UPDATE statement from this website to SET volume = volume + amount added, WHERE chemical ID = ID entered by the user; however, there appears to be some syntax errors in my code, more specifically at the UPDATE - SET - WHERE line:
public void IDEnter() {
try {
Class.forName("com.mysql.cj.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:8889/StockControlSystem","root","root");
Statement stmt = con.createStatement();
String sql = "Select * from Chemicals where `Chemical ID` ='" + txtChemical_ID.getText()+"'";
ResultSet rs = stmt.executeQuery(sql);
if(rs.next()) {
stmt.executeUpdate("UPDATE Chemicals" + "SET `Volume` = rs.getInt(Volume) + Integer.parseInt(AmountAdded.getText()) WHERE `Chemical ID` in (txtChemical_ID.getText())");
}
else {
JOptionPane.showMessageDialog(null, "Invalid chemical ID");
txtChemical_ID.setText(null);
}
} catch(Exception exc) {
exc.printStackTrace();
}
}
Since I'm still new to MySQL, can someone help me correct this? Thank you so much for your help!

Your whole query is badly formatted. Change your code to this:
stmt.executeUpdate("UPDATE Chemicals SET Volume = " +
rs.getInt(Volume) + Integer.parseInt(AmountAdded.getText())
+ " WHERE Chemical_ID in (" + txtChemical_ID.getText() + ")");
You cannot use ' single quotes when defining Column names in queries. Single quotes are used for string values!
Still, this would not be the best way to do this. use PreparedStatement!
This way:
String updateString = "UPDATE Chemicals SET Volume = ? WHERE Chemical_ID in (?)"; // Creation of the prepared statement, the ? are used as placeholders for the values
PreparedStatement preparedStatement = con.prepareStatement(updateString);
preparedStatement.setInt(1, rs.getInt(Volume) + Integer.parseInt(AmountAdded.getText())); // Setting the first value
preparedStatement.setString(2, txtChemical_ID.getText()); // Setting the second. I am supposing that this txtChemical_ID textField has values seperated by commas, else this will not work!
preparedStatement.executeUpdate();
If you need to read more for PreparedStatement there are a lot of great resources out there. They also protect against SQL injections.

I think your problem might be with the "rs.getInt(Volume)"
Yours:
"UPDATE Chemicals" + "SET `Volume` = rs.getInt(Volume)
+ Integer.parseInt(AmountAdded.getText())
WHERE `Chemical ID` in (txtChemical_ID.getText())"
Can you try this:
"UPDATE Chemicals" + "SET `Volume` = " +
Integer.parseInt(AmountAdded.getText()) + "
WHERE `Chemical ID` in (" + (txtChemical_ID.getText()) +")"

I need help selecting within a MySQL DateTime range in Java

I've got the following code in my app
String sql = "SELECT colA, colB, colC " +
"FROM " + tblName + " WHERE UserId = " + userId +
" AND InsertTimestamp BETWEEN " + lastDate +
" AND " + DataProcessor.TODAY + " ORDER BY UserId, Occurred";
try{
if(null == conn)
openDatabaseConnection();
PreparedStatement stmt = conn.prepareStatement(sql);
ResultSet rs = stmt.executeQuery(); <------- this is the line which throws the SQL exception
retArray = this.getArrayListFromResultSet(rs);
}catch(SQLException sqle){
JSONObject parms = new JSONObject();
eh.processSQLException(methodName, sqle, sql, parms);
}
So when I run my app in the debugger, I get this exception message
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 '00:00:00.0 AND 2014-08-20 00:00:00.0 ORDER BY UserId, Occurred' at line 1
I'm reasonably certain that there's simple and reasonable solution to this, but I have not been able to find it.
I've tried looking in the MySQL manual for a solution or a different format.
I've tried running my timestamps through a TIMESTAMP() functino and a DATE() function in the SQL, neither of which helped.
I pulled the fully formed SQL out of the Java code and ran it in MySQL Workbench with no issues, what-so-ever. So now I'm looking to the experts for help.

Dates in SQL must be enclosed within single quotes like strings.
As you're using a prepared statemtent, why you don't use '?' and stmt.setDate(...)?
String sql = "SELECT colA, colB, colC " +
"FROM " + tblName + " WHERE UserId = ?" +
" AND InsertTimestamp BETWEEN ?" +
" AND ? ORDER BY UserId, Occurred";
try {
if(null == conn) {
openDatabaseConnection();
}
PreparedStatement stmt = conn.prepareStatement(sql);
stmt.setInt(1, userId);
stmt.setDate(2, lastDate);
stmt.setDate(3, DataProcessor.TODAY);
ResultSet rs = stmt.executeQuery();
retArray = this.getArrayListFromResultSet(rs);
} catch(SQLException sqle) {
JSONObject parms = new JSONObject();
eh.processSQLException(methodName, sqle, sql, parms);
}
Anyway, I think you are setting the dates in the opposite order. You should put first 'today' then lastDate. Although I don't know your constraints...

Adding value to database

I use mysql workbench and netbeans
I have a table in mysql: Products that contains productsquantity=50 for example
in java, I want to add a value from text field to the database ( 50+value to add) please help, I use this code and didn't work
String url = "jdbc:mysql://localhost:3306/joebdd";
String driver = "com.mysql.jdbc.Driver";
String user = "root";
String pass = "12345";
//Error is here:
String sql = "UPDATE Produit " + " SET Quantity =
Quantity+'"+Integer.parseInt(jTextField4.getText())+"' " + "WHERE ProductName = ? " ;
try
{
Class.forName(driver).newInstance();
Connection conn = (Connection)DriverManager.getConnection(url,user,pass);
PreparedStatement pst = conn.prepareStatement(sql);
pst.setString(1, jTextField4.getText());
pst.setString(2, jTextField1.getText());
pst.executeUpdate();}
catch( Exception e){
JOptionPane.showMessageDialog(null, e);
}

Getting rid of the single quotes around the quantity that you're adding would fix your problem.
A better solution would be to use a ? in place of that quantity, and set it with setInt. So the SQL would be
UPDATE Produit SET Quantity = Quantity + ? WHERE ProductName = ?
and the line to set it would be
pst.setInt(1, Integer.parseInt(jTextField4.getText()));

Inserting values in specific row sql java

"SELECT * FROM PlayerClass WHERE Username = '" + p.getName() + "'"
So I have selected the specific row and how would I go about inserting a value in column ExColumn in the same exact row?

If you're allowed to use JDBC and PreparedStatement, I would suggest you do this:
String sql = "UPDATE PlayerClass SET ExColumn = ? WHERE Username = ?";
PreparedStatement ps = connection.prepareStatement(sql);
ps.setObject(1, exColumnValue); // exColumnValue is the data you're trying to insert
ps.setString(2, p.getName());
ps.executeUpdate();
This way you'll be avoiding SQL injection attacks.

You have to use UPDATE
"Update PlayerClass set Username = '" +someValue + "'"
That will update all rows
To update secific rows with some condition ,add where clause.
"Update PlayerClass set Username = '" +someValue + "'
WHERE Username = '" + p.getName() + "'"

May be your are trying to update specific row. then this will help you
UPDATE PlayerClass SET ExColumn='YOUR_INSERTION_DATA_IN_THIS'
WHERE Username = 'XYZ'