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Why ResultSet don't return the data from MySQL

I'm tying to get an image from MySQL database and show in a JLabel, but when I execute the query and try to get the bytes from the ResultSet it returns an empty array.
I tested the connection, and it is working, tested the query and its also working.
try {
conn = getConnection();
pst = conn.prepareStatement("select * from imagem where serial_imagem = 123658");
rs = pst.executeQuery()
if (rs.next()) {
image = rs.getBytes("img_imagem");
}
}catch (Exception e) {
e.printStackTrace();
}

The code does not close and thus leaks resources. The somewhat ugly Try-With-Resources syntax ensures closing connection, statement and result set, even on returning/exception.
One could make explicit with Optional whether the image was found in the table or not.
Optional.of also guarantees that the field in the database must not contain an SQL NULL value.
Optional<byte[]> loadImageFromDatabase(String imageM) throws SQLException {
String sql = "select img_imagem from imagem where serial_imagem = ?";
try (Connection conn = getConnection();
PreparedStatement pst = conn.prepareStatement(sql)) {
pst.setString(1, imageM);
try (ResultSet rs = pst.executeQuery()) {
if (rs.next()) {
return Optional.of(rs.getBytes(1)); // ofNullable
} else {
return Optional.empty();
}
}
}
}
Usage:
try {
Optional<byte[]> img = loadImageFromDatabase(jtextField1.getText().trim());
img.ifPresent(image -> {
...
});
} catch (SQLException e) {
There is still to remark that I personally do not often use ResultSet.getBytes, but rather getInputStream. Depends on the image size and creation code.

Sql code give invalid SQL statement in Java but it works in SqlDeveloper

I tried to make crud , but insert statement do not work from code
try {
java.sql.Date sqlDate = new java.sql.Date(date.getTime());
conn2 = DriverManager.getConnection(dbURL2, username, password);
String sql="INSERT INTO Produce(name,description,Produce_Date,Price,CATEGORY_ID,Person_ID)VALUES('"+name+"','"+description+"',TO_DATE('"+sqlDate+"', 'yyyy-mm-dd'),"+price+","+category_Id+","+person_id+")";
System.out.println(sql);
stmt = conn2.createStatement();
ResultSet rs = stmt.executeQuery(sql);
while (rs.next()) {
System.out.println(rs.getString("name"));
}
if (conn2 != null && !conn2.isClosed()) {
conn2.close();
}
} catch (SQLException ex) {
ex.printStackTrace();
}
I made a System.out.println to see my sql and to execute it to understand where is the problem, this is my String, and it works in sqlDeveloper:
INSERT INTO Produce(name,description,Produce_Date,Price,CATEGORY_ID,Person_ID)VALUES('ew','rrr',TO_DATE('2018-11-14', 'yyyy-mm-dd'),12.0,2,2)

you are using insert SQL query to retrieve result.
I believe to retrieve name you need to execute select statement

Hive 2 JDBC PreparedStatement throws an error cannot recognize input near '?' '<EOF>' '<EOF>' in expression specification

try {
Class.forName("org.apache.hive.jdbc.HiveDriver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
System.exit(1);
}
String query = "SELECT spd_field_label_id FROM RAL WHERE SUBJECT_USER_ID = ?";
PreparedStatement stmt = null;
Connection con = null;
boolean testCasePassed = false;
try {
con = DriverManager.getConnection("jdbc:hive2://localhost:10000/default", "", "");
stmt = con.prepareStatement(query);
stmt.setString(1, "USR-44");
ResultSet resultSet = stmt.executeQuery(query);
Assert.assertNotNull(resultSet);
while (resultSet.next()) {
testCasePassed = true;
System.out.println("=======Test =========" + resultSet.getString("spd_field_label_id"));
}
} finally {
if (stmt != null) {
stmt.close();
}
if (con != null) {
con.close();
}
}
return testCasePassed;
RAL is a simple Hive table with String type columns spd_field_label_id and SUBJECT_USER_ID.
Simple PreparedStatement using Hive2 throwing an Error stacktrace below. Any pointers on what could be wrong? Same query works fine when using Statement instead of PreparedStatement and without using ? for parameter binding.
org.apache.hive.service.cli.HiveSQLException: Error while compiling statement: FAILED: ParseException line 1:62 cannot recognize input near '?' '<EOF>' '<EOF>' in expression specification
at org.apache.hive.jdbc.Utils.verifySuccess(Utils.java:264)
at org.apache.hive.jdbc.Utils.verifySuccessWithInfo(Utils.java:250)
at org.apache.hive.jdbc.HiveStatement.runAsyncOnServer(HiveStatement.java:309)
at org.apache.hive.jdbc.HiveStatement.execute(HiveStatement.java:250)
at org.apache.hive.jdbc.HiveStatement.executeQuery(HiveStatement.java:434)

stmt.executeQuery(query);
You're using the wrong method. You've already prepared the statement. It is ready to execute. It should be:
stmt.execute();

SQL Lite Query (between in dates) doesn't work

in my small test program I have some SQL Queries. The first SELECT * FROM kilometer; works properly and returns all the columns in the table. So in Java embedded, ResultSet rs = stmt.executeQuery("SELECT * FROM kilometer;"); returns an ResultSet which is not empty.
Now I wanted to get only the rows within a specific date. But my embedded query ResultSet rs = stmt.executeQuery("SELECT * FROM kilometer WHERE datum BETWEEN '2016-01-01' AND '2016-12-31';"); returns an empty ResultSet. But I've tested it online and it worked properly. Where is my mistake? I've consulted already some pages like this, but I can't find the mistake.
I am using SQLite 3.15.1 and Java SE 8.
Full java code:
public ArrayList<Strecke> getErgebnisse(final String startzeitpunkt, final String zielzeitpunkt) {
ArrayList<Strecke> strecken = new ArrayList<>();
try {
try {
if (connection != null) {
}
connection = DriverManager.getConnection("jdbc:sqlite:" + DB_PATH);
if (!connection.isClosed())
} catch (SQLException e) {
throw new RuntimeException(e);
}
Statement stmt = connection.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM kilometer WHERE datum BETWEEN '2016-01-01' AND '2016-12-31';");
while (rs.next()) {
strecken.add(new Strecke(Instant.ofEpochMilli(rs.getDate("datum").getTime()).atZone(ZoneId.systemDefault()).toLocalDate(), rs.getString("startort"), rs.getString("zielort"), rs.getDouble("kilometer")));
}
rs.close();
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
return strecken;
}

First of all I would recommend that you use prepared statements while executing your queries instead of passing the query directly as a string......secondly I believe the problem here is that you are passing the date as a string in quotes and not a date.....I think that is the issue here. You would need to use sqllites datetime functions for this....

Java JDBC Incorrect Syntax Error

I have this method to load the objects, however when I am running the sql code it is giving me a Syntax error.
public void loadObjects() {
Statement s = setConnection();
// Add Administrators
try {
ResultSet r = s.executeQuery("SELECT * FROM Administrator;");
while (r.next()) {
Administrator getUser = new Administrator();
getUser.ID = r.getString(2);
ResultSet r2 = s.executeQuery("SELECT * FROM Userx WHERE ID= {" + getUser.ID + "};");
getUser.name = r2.getString(2);
getUser.surname = r2.getString(3);
getUser.PIN = r2.getLong(4);
JBDeveloping.users.administrators.add(getUser);
}
} catch (Exception e) {
System.out.println(e);
}
}
I have tried inserting the curly braces as stated in other questions, but I am either doing it wrong or it doesn't work.
This method should be able to load all administrators but I believe it is only inserting half of the ID.
The ID that it gets, consists of numbers and char; example "26315G"
the Error -
com.microsoft.sqlserver.jdbc.SQLServerException: Incorrect syntax near '26315'.
Edit -
private java.sql.Connection setConnection(){
java.sql.Connection con = null;
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
String url = "jdbc:sqlserver://" + host + ";DatabaseName=" + database + ";integratedSecurity=true;";
con = DriverManager.getConnection(url, username, password);
} catch(Exception e) {
System.out.println(e);
}
return con;
}
public void loadObjects() {
java.sql.Connection con = setConnection();
// Add Administrators
try {
PreparedStatement sql = con.prepareStatement("SELECT * FROM Administrator");
ResultSet rs = sql.executeQuery();
while (rs.next()) {
Administrator getUser = new Administrator();
getUser.ID = rs.getString(2);
PreparedStatement sql2 = con.prepareStatement("SELECT * FROM Userx WHERE ID=?");
sql2.setString(1, getUser.ID);
ResultSet r2 = sql2.executeQuery();
getUser.name = r2.getString(2);
getUser.surname = r2.getString(3);
getUser.PIN = r2.getLong(4);
JBDeveloping.users.administrators.add(getUser);
}
} catch (Exception e) {
System.out.println(e);
}
}

Actually it is not the way to do that in JDBC. That way, even if you sort your syntax error, your code is prone to sql injection attacks.
The right way would be:
// Let's say your user id is an integer
PreparedStatement stmt = connection.prepareStatement("select * from userx where id=?");
stmt.setInt(1, getUser.ID);
ResultSet rs = stmt.executeQuery();
This way you are guarded against any attempt to inject SQL in your application request parameters

First of all: if you use concurrently result-sets, you must use separate statements for each one of them (you can not share Statement s between two r and r2). And more, you lack r2.next() before reading from it.
On the other hand: it would be much more effective to use PreparedStatement in the loop that to rewrite the query all the time.
So I'd go for something like this:
public void loadObjects() {
try (
Statement st = getConnection().createStatement();
//- As you read (later) only id, then why to use '*' in this query? It only takes up resources.
ResultSet rs = st.executeQuery("SELECT id FROM Administrator");
PreparedStatement ps = getConnection().prepareStatement("SELECT * FROM Userx WHERE ID = ?");
ResultSet r2 = null;
) {
while (rs.next()) {
Administrator user = new Administrator();
user.ID = rs.getString("id");
ps.setInt(1, user.ID);
r2 = ps.executeQuery();
if (r2.next()) {
user.name = r2.getString(2);
user.surname = r2.getString(3);
user.PIN = r2.getLong(4);
JBDeveloping.users.administrators.add(user);
}
else {
System.out.println("User with ID=" + user.ID + " was not found.");
}
}
}
catch (Exception x) {
x.printStacktrace();
}
}
Please note use of Java7 auto-close feature (you didn't close resources in you code). And last note: until you are not separating statements in your queries, as to JDBC documentation, you should not place ';' at the end of statements (in all cases you shouldn't place ';' as the last character in you query string).

You should not use {} and you should not append parameters into a SQL query like this.
Remove the curly braces and use PreparedStatement instead.
see http://www.unixwiz.net/techtips/sql-injection.html