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Query executed twice (by error) in Java with unwanted values

I'm using JFreeChart to create a chart in Java and MySQL.
When I try to insert my values in another table the query seems to be executed twice since I end up with the same timestamps multiple times...
Here's a part of my code :
private JDBCXYDataset createDataset() {
try {
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:bd?serverTimezone=UTC","MySQL", "MySQL");
conn.setAutoCommit(false);
SQLException savedException = null;
Statement st = conn.createStatement();
st.execute("DROP TABLE IF EXISTS test ");
st.execute("create table test(Table timestamp, Table float,Table float)");
String Date_Debut = "2020-06-25 00:00:00";
String Date_Fin = "2020-06-26 00:00:00";
String sql1 = "INSERT INTO test (Table ,Table ,Table ) "
+ "SELECT Table ,Table ,Table "
+ "FROM Table "
+ "WHERE Table BETWEEN ? AND ? ";
try ( PreparedStatement ps = conn.prepareStatement(sql1)){
ps.setString(1,Date_Debut);
ps.setString(2, Date_Fin);
ps.executeUpdate();
ps.close();
JDBCXYDataset jds = new JDBCXYDataset(conn);
st.close();
jds.executeQuery("SELECT Table ,Table ,Table FROM test");
conn.commit();
return jds;
} catch (SQLException ex) {
savedException = ex;
conn.rollback();
} finally {
conn.setAutoCommit(true);
if(savedException != null) {
throw savedException;
}
}
} catch (SQLException ex1) {
}
return null;
}
EDIT : Actually it seems like the errors where comming directly from the database, the moderators can delete this post if they want. However I keep Trashgod's response validated as it was more than helpful.
For everyone that might come here with a similar issue, inspect in detail your database first to see if it isn't comming from there instead of your code.

Chasing down anomalies in data is arduous, but JFreeChart can at least make the result easier to visualize. Some heuristics for testing:
To verify that the the presumed duplicates in your tabular listing are indeed duplicates, format the timestamps to include milliseconds, e.g. add an S to a SimpleDateFormat or A to a DateTimeFormatter.
For study, temporarily pass the query directly to JDBCXYDataset, and add an ORDER BY clause (untested):
jds.executeQuery(
"SELECT Date_Heure, PV, SV FROM cmd3 "
+ "WHERE Date_Heure BETWEEN "
+ "2020-06-25 00:00:00 AND 2020-06-26 00:00:00 "
+ "ORDER BY Date_Heure");
Enable tooltips in your ChartFactory, as you did here, to see data values in situ. This may suggest additional conditions for your WHERE clause, e.g. PV BETWEEN 5.1 AND 5.9.
Use the interactive JFreeChart pan/zoom controls, discussed here to examine the data; add suitable buttons, shown here, if it will make it easier for colleagues to see your findings.
By design, JDBCXYDataset executes a query defined by a String. If your design needs to display data from a query defined by a PreparedStatement, you can use the existing implementation as a guide.
public class PreparedDataset extends AbstractXYDataset
implements XYDataset, TableXYDataset, RangeInfo {
private final PreparedStatement ps;
public PreparedDataset(PreparedStatement ps) {
this.ps = ps;
}
…
}

2 SQL queries in one try/catch. Not working

Basically, I have to show a list with the data from a database table [that part is working] and afterwards I have to show the highest Date [a date variable in the table]. The second part is not working no matter what I do.
Here's the code
try {
String SQL = "SELECT * FROM tb_rafael";
ResultSet rs = BD.consultar(SQL);
String tab = "";
int numReg = 0;
while (rs.next()) {
tab+="<TR>";
tab+="<TD>" + rs.getString("nme_rafael") + "</TD>";
tab+="<TD>" + rs.getString("dta_rafael") + "</TD>";
tab+="</TR>";
numReg++;
//mDat = rs2.getString("dta_rafael");
}
rs.close();
dados.put("DADOS", tab);
dados.put("NUM_REG", String.valueOf(numReg));
//Pegar Data Maior
String SQL2 = "SELECT MAX(dta_rafael) FROM tb_rafael";
ResultSet rs2 = BD.consultar(SQL2);
String mDat = "";
//while(rs2.next()){
mDat = rs2.getString("dta_rafael");
//}
rs2.close();
dados.put("MDA", mDat);
} catch (Exception ex) {
dados.put("MSG", "Erro: " + ex.getMessage());
}
What you want to look at is past the commentary line "Pegar Data Maior". That's the part that is not working. I've tried adding a while, using a different ResultSet, using the same ResultSet and none of those worked. I know it's not an issue with the SQL query since I tested it with the workbench and it returned me the data I want.
To be more specific, I don't get an error message or anything, the dados.put simply does not work and I get just this:
How the HTML code looks:
The data should show up where the {MDA} is. Anyone have any ideas?

The query SELECT MAX(dta_rafael) FROM tb_rafael may not return a column name, which you later try to retrieve, rs2.getString("dta_rafael");
I'd change the query to SELECT MAX(dta_rafael) AS Max_date..., and reference to MAX_date thereafter.

Using Java, what is the best way to update a column in every row with values from an array? (SQLite)

Today is my first day using SQLite. I am using Java to interact with an SQLite database that contains fields called ID, NAME, CITY. I would like to take every record in the database and replace the CITY field with a value from an array. Here is what I tried, but realized right away it was wrong. I believe the query is replacing every record 3 times which gives the result that each CITY field is 'Compton'. I am not sure on what is a good or efficient way to do this.
public void update(String cities[]) throws SQLException {
PreparedStatement updateCity = null;
Connection con = null;
String updateString = "update SUPPLIERS set CITY = ?";
try {
Class.forName("org.sqlite.JDBC");
con = DriverManager.getConnection("jdbc:sqlite:suppliers.db);
con.setAutoCommit(false);
updateCity = con.prepareStatement(updateString);
for (int i = 0; i < cities.length; i++) {
updateCity.setString(1, cities[i]);
updateCity.executeUpdate();
con.commit();
}
} catch (Exception e) {
e.printStackTrace();
if (con != null) {
try {
System.err.print("Transaction is being rolled back");
con.rollback();
} catch (SQLException excep) {
excep.printStackTrace();
}
}
} finally {
if (updateCity != null) {
updateCity.close();
}
con.setAutoCommit(true);
con.close();
}
}
I was calling the method like so instance.update(new String[]{"san diego", "los angeles", "Compton"});. I would like to know how to go about doing this with a PreparedStatement if possible, but if this is not the best way to go, please post an alternative suggestion.
Note: This is not my code, it is code taken from SQLite Java Tutorials.

Your update statement will update ever record in the table each time it is called. If you want the statement to update only one record at a time, you will need to change your update statement to something like this:
update SUPPLIERS set CITY = ? where ID = ?
If you want to update all records, you'll need to execute a query to get all of the IDs. A query like this should work:
select ID from SUPPLIERS
Then for each ID returned, call the update statement using that ID and whatever city you wish to update the record with.

java load values from database into comboBox

Hi my aim is to load combobox with vaules from a database the code below works fine with one issue i get two of the first item so what must i do to prevent this
public void loadCombos() {
try {
try {
String cs = "jdbc:mysql://localhost:3307/booksalvation6";
String user = "root";
String password = "letmein";
jComboBox2.removeAllItems();// make sure old data gone
PreparedStatement pstpost;
ResultSet rspost;
conCombos = DriverManager.getConnection(cs, user, password);
for (int i = 1; i < 11; i++) {
String querypost = "select * from post "
+ "WHERE postage_id =" + i;
// load postage selections
pstpost = conCombos.prepareStatement(querypost);
rspost = pstpost.executeQuery();
while (rspost.next()) {
String Mypost = rspost.getString(6);
jComboBox2.addItem(Mypost);
}
}
} catch (SQLException ex) {
Logger.getLogger(BasicFrame.class.getName()).log(Level.SEVERE, null, ex);
}
conCombos.close();
} catch (SQLException ex) {
Logger.getLogger(BasicFrame.class.getName()).log(Level.SEVERE, null, ex);
}
}

You are using PreparedStatement but not in proper way.
Since you are looking only for one column to fetch all the column values which have postage_id between 1 to 10.
You can achieve it in single query:
select unique(combo_value_column_name) from post
where postage_id>=? and postage_id<=?
set the parameter via calling PreparedStatement#setInt(index,value) set it 1 and 10.
Just fetch single column and only unique values.
It's better explained under Java Tutorial on Using Prepared Statements
Instead of calling JComboBox#addItem() first prepare the whole list then finally set it once.
Read more...
Final Note: Follow Java Naming Convention.

Mysql+JDBC+Linux: executeQuery returns empty result set when it shouldn't

I have following code:
public boolean updateDatabase(long houseValue, List<Users> userList)
{
boolean result = false;
Connection conn = null;
PreparedStatement stmtUpdateUsers = null;
PreparedStatement stmtQueryHouse = null;
PreparedStatement stmtUpdateHouse = null;
ResultSet rs = null;
String updateUsers = "UPDATE users SET money = ? WHERE username = ?";
String queryHouse = "SELECT * FROM house WHERE house_id = ?";
String updateHouse = "UPDATE house SET house_money = ? WHERE house_id = ?";
try
{
conn = getConnectionPool().getConnection();
conn.setAutoCommit(false);
stmtUpdateUsers = conn.prepareStatement(updateUsers);
...
// Here is some code that updates Users table in a short loop
...
stmtQueryHouse = conn.prepareStatement(queryHouse);
stmtQueryHouse.setInt(1, 1);
rs = stmtQueryHouse.executeQuery();
if(rs.next())
{
long houseMoney = rs.getLong("house_money");
houseMoney += houseValue;
stmtUpdateHouse = conn.prepareStatement(updateHouse);
stmtUpdateHouse.setLong(1, houseMoney);
stmtUpdateHouse.setInt(2, 1);
stmtUpdateHouse.executeUpdate();
}
else
{
throw new SQLException("Failed to update house: unable to query house table");
}
conn.commit();
result = true;
}
catch(SQLException e)
{
logger.warn(getStackTrace(e));
try{conn.rollback();}catch(SQLException excep)
{
logger.warn(getStackTrace(excep));
}
}
finally
{
DbUtils.closeQuietly(rs);
DbUtils.closeQuietly(stmtQueryHouse);
DbUtils.closeQuietly(stmtUpdateUsers);
DbUtils.closeQuietly(stmtUpdateHouse);
try { conn.setAutoCommit(true); } catch (SQLException e) { /* quiet */ }
DbUtils.closeQuietly(conn);
}
return result
}
This method can be called from multiple threads, house table is just a one row table which holds total earned money. It gets updated by different threads.
Problem is that stmtQueryHouse.executeQuery() returns empty set, and it should not happen, because house table always have (since database creation) one single row that gets updated (only house_money column is updated).
When I run this code on windows (JDBC driver + mysql 5.5.13) it works fine, but when I run it on CentOS (same JDBC driver + mysql 5.1.57) it returns empty result set very often (if not always). Any idea what is going wrong or how could I check where is the problem? Maybe I should use select for update, but then why it works on windows and not on linux? I appreciate any help. Thanks in advance.

Look in the mysql general query log for any errors?
I realize this isnt your question per se, but if you have another table with just a single row for each House, it sounds to me that it would make more sense to move house_money into your main house table

I'd say this one method is doing far too much.
I'd pass in the Connection to three separate methods and manage the transaction outside all of them.
I'd wonder if there's an optimization that would eliminate one of the UPDATES.
I'd want to batch all these so I didn't do a round trip for each and every user. It'll perform poorly as the # of users increases.