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Android :java.sql.SQLException: No current row in the ResultSet

I am getting the following error when i try to execute my query(s),but i don't know why it gives me the following error every time i try to execute my query(s).The error also appears in my logcat and not in a toast as i expected.
here is my code!!
#Override
protected String doInBackground(String... strings) // Connect to the database, write query and add items to array list
{
runOnUiThread(new Runnable() {
public void run() {
try {
Connection conn = connectionClass.CONN(); //Connection Object
if (conn == null) {
success = false;
msg = "Sorry something went wrong,Please check your internet connection";
} else {
// Change below query according to your own database.
Date c = Calendar.getInstance().getTime();
SimpleDateFormat df = new SimpleDateFormat("yyyy/mm/dd");
String formattedDate = df.format(c);
System.out.println("it isssssssssssssssssssssssssssssssssssssssssaaaaaaaaaaaaaaaaaaaa"+getIntent().getStringExtra("nameid"));
String query = "Insert into CustomerSupportChat values('" + formattedDate + "','" + themsg.getText().toString() + "','Customer','3','"+getIntent().getStringExtra("nameid")+"','1','1') " +
"Select MessageID,MessageDate,MessageText,SenderType,MessageRecieved,MessageReaded,Users_Login_Data.Username,StoresData.StoreEnglishName,StoresData.StoreArabicName FROM " +
"CustomerSupportChat INNER JOIN Users_Login_Data ON " +
"CustomerSupportChat.CustomerID = Users_Login_Data.CustomerID INNER JOIN StoresData ON " +
"CustomerSupportChat.StoreID = StoresData.StoreID";
String query2 =
"Select MessageID,MessageDate,MessageText,SenderType,MessageRecieved,MessageReaded,Users_Login_Data.Username,StoresData.StoreEnglishName,StoresData.StoreArabicName FROM " +
"CustomerSupportChat INNER JOIN Users_Login_Data ON " +
"CustomerSupportChat.CustomerID = Users_Login_Data.CustomerID INNER JOIN StoresData ON " +
"CustomerSupportChat.StoreID = StoresData.StoreID Where SenderType = 'Store'";
Statement stmt = conn.createStatement();
Statement stmt2 = conn.createStatement();
ResultSet rs = stmt.executeQuery(query);
ResultSet rs2 = stmt2.executeQuery(query2);
if (rs != null) // if resultset not null, I add items to itemArraylist using class created
{
while (rs.next()) {
try {
itemArrayList.add(new ClassListChat(rs.getString("MessageDate"), rs.getString("MessageText"), rs.getString("SenderType"), rs2.getString("MessageText")));
themsg.setText("");
} catch (Exception ex) {
ex.printStackTrace();
}
}
msg = "Found";
success = true;
} else {
msg = "No Data found!";
success = false;
}
}
} catch (Exception e) {
e.printStackTrace();
Writer writer = new StringWriter();
e.printStackTrace(new PrintWriter(writer));
msg = writer.toString();
Log.d("Error", writer.toString());
success = false;
}
}
});
return msg;
}
I have tried removing while and replacing it with if statement but it showed me the same error.
I also tried my query on mssql and it executed successfully.
EDIT I solved it by changing the date format to MM/dd/yyyy.
But now i get the following error:
java.sql.SQLException: No current row in the ResultSet.
Any ideas?

Looks like there is no null check for rs2 in the below line so could throw that error:
itemArrayList.add(new ClassListChat(rs.getString("MessageDate"), rs.getString("MessageText"), rs.getString("SenderType"), rs2.getString("MessageText")));
Also a better way to check for ResultSet not returning anything is like this:
if (rs.next() == false){
msg = "No Data found!";
success = false;
} else {
do {
// add items to itemArraylist...
} while (rs.next());
}
Read more: https://javarevisited.blogspot.com/2016/10/how-to-check-if-resultset-is-empty-in-Java-JDBC.html#ixzz6KIFZZHNB

Java sqlite row disappear after Select query

I have a sqlite db file created by other program, and checked everything is fine.
Then after doing select query to get some data, some of the row disappear after this process. I tried to use prepareStatement and though it worked but this remained.
my code
private ForecastTableItem selectItemPrepareStatement(String tableName, String columnName, String name) {
ForecastTableItem item = null;
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
Class.forName("org.sqlite.JDBC");
conn = DriverManager.getConnection("jdbc:sqlite:" + dbLocation);
System.out.println("Selecting item from tableName: "+tableName + " of col: "+columnName + " : "+name);
String query = "SELECT * FROM " + tableName + " WHERE " + columnName + "=? COLLATE NOCASE";
pstmt = conn.prepareStatement(query);
pstmt.setString(1, name);
rs = pstmt.executeQuery();
if (rs.next()) {
if (tableName.equalsIgnoreCase("mainTable")) {
item = new ForecastTableItem();
item.setId(rs.getInt("Id"));
item.setTitle(rs.getString("title"));
item.setLink(rs.getString("link").toLowerCase());
item.setPositionType(rs.getString("positionType"));
item.setPackageName(rs.getString("packageName"));
item.setCsvFilePath(rs.getString("csvFilePath"));
item.setSubpackageName(rs.getString("subpackageName"));
item.setTimeFrame(rs.getString("timeFrame"));
item.setForecastDate(rs.getString("forecastDate"));
item.setTargetDate(rs.getString("targetDate"));
}
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally{
if(pstmt != null) try{ pstmt.close();} catch(SQLException e){};
if(rs != null) try{ rs.close();} catch(SQLException e){};
if(conn != null) try{ conn.close();} catch(SQLException e){};
}
return item;
}

after COLLATE NOCASE use semi-column
"SELECT * FROM " + tableName + " WHERE " + columnName + "= ? COLLATE NOCASE;";

SQL database not populating via Java by using execute/addBatch

I currently have a very large file which contains a few million lines of entries, and want them inserted into a database. The connection established from java to SQL works as I have tried inserting the data singularly and it works, however, when I switched to using executeBatch and addBatch, it seems to loop though but not populating anything into my database.
Code is as follows:
import java.io.BufferedReader;
import java.io.FileReader;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.SQLException;
public class fedOrganiser6 {
private static String directory = "C:\\Users\\x\\Desktop\\Files\\";
private static String file = "combined.fed";
private static String mapperValue = "";
public static void main(String[] args) throws Exception {
Connection conn = null;
try {
BufferedReader mapper = new BufferedReader(new FileReader(directory + file));
String dbURL = "jdbc:sqlserver://localhost\\SQLExpress;database=TIMESTAMP_ORGANISER;integratedSecurity=true";
String user = "sa";
String pass = "password";
conn = DriverManager.getConnection(dbURL, user, pass);
if (conn != null) {
DatabaseMetaData dm = (DatabaseMetaData) conn.getMetaData();
System.out.println("Driver name: " + dm.getDriverName());
System.out.println("Driver version: " + dm.getDriverVersion());
System.out.println("Product name: " + dm.getDatabaseProductName());
System.out.println("Product version: " + dm.getDatabaseProductVersion());
System.out.println("clearing database");
conn.createStatement().executeUpdate("truncate table TimestampsStorage");
System.out.println("bulk insert into database");
System.out.println("complete");
int i = 0;
int records = 0;
String query = "INSERT INTO TimestampsStorage " + "values(" + "'" + mapperValue.toString() + "'"+ ")";
conn.prepareStatement(query);
for (mapperValue = mapper.readLine(); mapperValue != null; mapperValue = mapper.readLine()) {
i++;
records++;
System.out.println("Batching " + records + " records...");
conn.createStatement().addBatch(query);
if (i == 100000) {
conn.createStatement().executeBatch();
i = 0;
}
}
}
conn.createStatement().executeBatch();
conn.createStatement().close();
System.out.print("Done");
} catch (SQLException ex) {
ex.printStackTrace();
} finally {
try {
if (conn != null && !conn.isClosed()) {
conn.close();
}
} catch (SQLException ex) {
ex.printStackTrace();
}
}
}
}

createStatement() creates a new statement object, so you're execute a different statement than the one you're batching on. You should create the PreparedStatement once, add several batches to it, and then execute on the same object:
String query = "INSERT INTO TimestampsStorage VALUES (?)";
PreparedStatement ps = conn.prepareStatement(query);
for (mapperValue = mapper.readLine();
mapperValue != null;
mapperValue = mapper.readLine()) {
i++;
records++;
System.out.println("Batching " + records + " records...");
ps.setString(1, mapperValue);
ps.addBatch();
if (i == 100000) {
ps.executeBatch();
i = 0;
}
}

I think you are a bit mistaken on how batch processing for JDBC works.
You are creating a new Statement each time you call conn.createStatement().
Instead, you will want to use a PreparedStatement. First, change your query to include a ? where you want your values to go.
String query = "INSERT INTO TimestampsStorage VALUES(?)";
Then, when you call conn.prepareStatement(query), store the returned PreparedStatement.
PreparedStatement ps = conn.prepareStatement(query);
This PreparedStatement will then 'remember' your query, and you can simply change the values you want where the ? is on each iteration of your loop.
ps.setString(1, mapperValue);
The setString method will take your mapperValue and use it instead of the first ? it finds in your query (since you pass in the index 1).
Then, instead of calling conn.createStatement().addBatch(), you would call ps.addBatch().
Then, outside of your loop, you can call ps.executeBatch(). (There is no need to call this inside your loop, so you can remove your if (i == 100000) condition).
Finally, if you are using Java 7+, you can use a try with resources, so that you don't need to worry about closing the PreparedStatement or Connection in a finally block.
Here is what your end result should look like.
String query = "INSERT INTO TimestampsStorage VALUES (?)";
try (Connection con = DriverManager.getConnection(dbURL, user, pass); PreparedStatement ps = con.prepareStatement(query);) {
for (mapperValue = mapper.readLine(); mapperValue != null; mapperValue = mapper.readLine()) {
records++;
ps.setString(1, mapperValue);
ps.addBatch();
}
System.out.println("Executing batch of " + records + " records...");
ps.executeBatch();
} catch (SQLException ex) {
//handle exception
}

you are throwing away the prepared statement
String query = "INSERT INTO TimestampsStorage VALUES (?)";
PreparedStatement statement = conn.prepareStatement(query);
for (mapperValue = mapper.readLine(); mapperValue != null; mapperValue = mapper.readLine()) {
i++;
records++;
System.out.println("Batching " + records + " records...");
statement.setString(1,mapperValue);
statement.addBatch();
if (i == 100000) {
statement.executeBatch();
i = 0;
}

to check whether the search element isn't available in DB

I'm using phpmy admin and I need to Display "Not Found" message in case searching element is not found in the DB.
Used code is here.
Connection c = DBconnect.connect();
Statement s = c.createStatement();
String e = txtempId.getText();
ResultSet rs = s.executeQuery("SELECT * FROM nonacademic WHERE empId='" +e+ "'");
I used this method to search empId ,if empId is not available in db I need to display a message.Please give me a solution how to detect, if empId is not available in DB.

if (rs != null)
{
out.println("result set has got something");
while (rs.next())
{
//I am processing result set now
}
}
else
{
out.println("Not Found");
}

Use if statement like this
Connection c = DBconnect.connect();
Statement s = c.createStatement();
String e = txtempId.getText();
ResultSet rs = s.executeQuery("SELECT * FROM nonacademic WHERE empId='" +e+ "'");
if(rs.next())
{
do
{
// If there is data, then process it
}
while(rs.next());
}
else
System.out.println("Not Found");

Added parse of text to integer, assuming empId is an integer.
int empId = Integer.parseInt(txtempId.getText());
try (Connection c = DBconnect.connect()) {
String sql = "SELECT *" +
" FROM nonacademic" +
" WHERE empId = ?";
try (Statement s = c.prepareStatement(sql)) {
s.setInt(1, empId);
try (ResultSet rs = s.executeQuery()) {
if (! rs.next()) {
// not found
} else {
// found, call rs.getXxx(...) to get values
}
}
}
}

Just use the basic simple if & else statement. If the ResultSet is "null" or it doesn't contain any record display the Message otherwise read data & display.
Connection c = DBconnect.connect();
Statement s = c.createStatement();
String e = txtempId.getText();
ResultSet rs = s.executeQuery("SELECT * FROM nonacademic WHERE empId='" +e+ "'");
if(rs.next())
// record found do the processing
else
System.out.println("Not Found");

String e = txtempId.getText();
String sql="select *from nonacademic where empId='"+ e+"' ";
try {
boolean status=DatabaseConnection.checkValue(sql);
if (status) {
JOptionPane.showMessageDialog(null,
"This id is available");
} else {
JOptionPane.showMessageDialog(null,
"Not found");
}
} catch (Exception e) {
}
This method return check whether the search element is exist or not
public static boolean checkValue(String sql) throws Exception {
boolean b = false;
ResultSet rst = null;
Statement st = getStatement();
rst = st.executeQuery(sql);
if (rst.next()) {
b = true;
}
return b;
}

How to Getting a List from MS Sql Server Using Java

I have a problem, I cannot get my list from MS SQL Server Database.
This is my code:
public List<Location> showLocations(String nmlocation) {
List<Location> location = new ArrayList<Location>();
try {
String sql = "SELECT deskripsi FROM T_Place WHERE ID_Place='%" + nmlocation + "%'";
PreparedStatement statement = (PreparedStatement) dm.logON().prepareStatement(sql);
boolean result = statement.execute();
if (result) {
ResultSet rs = statement.getResultSet();
int i = 0;
while (rs.next())
{
Location loc = new Location(rs.getString("deskripsi"));
System.out.println(loc);
location.add(loc);
i++;
}
rs.close();
}
} catch (SQLException sqle) {
System.out.println("Error on Listing Location Data showLocation Status : " + sqle.getSQLState()
+ " \n Error Message : " + sqle.getMessage()
+ " \n Error State : " + sqle.toString());
}
return location;
}
But it shows empty resultset. How to fix it? thanks in advance.