How to Load "result set" one by one into table view? - java

I have loaded millions of rows of data from 5 tables in database. I want to display the loaded data into a tableview. It takes a long time to load all the records(sometimes all of them don't fit into memory). I want to make it so that I can load a resultSet, display it, load a second one, and so on. Is this possible? My code as of now:
#FXML
private TableView<Vysledok_hladania> table;
#FXML
private TableColumn<Vysledok_hladania, String> Nazov_hotela, Adresa, Krajina, Mesto, Hviezdicky, Cena, Typ_izby, Pocet_izieb;
#FXML
void vyhladajInfo(ActionEvent event){
table.getItems().clear();
try {
Connection con = Runner.getConnection();
con.setAutoCommit(false);
String query = "SELECT h.\"Nazov hotela\", k.\"Nazov krajiny\", m.\"Nazov mesta\", h.\"Adresa hotela\", h.\"Hviezdicky\", p.\"Cena pobytu\", i.\"Typ izby\", h.\"Pocet izieb\" FROM hotel h " +
"inner JOIN izba i ON i.\"ID hotela\" = h.\"ID hotela\" " +
"inner JOIN krajina k ON k.\"ID krajiny\" = h.\"ID krajiny\" " +
"inner JOIN mesto m ON m.\"ID mesta\" = h.\"ID mesta\" " +
"inner JOIN pobyt p ON p.\"ID hotela\" = h.\"ID hotela\" " +
"WHERE h.\"Nazov hotela\" = ? " +
"AND k.\"Nazov krajiny\" = ? " +
"AND h.\"Hviezdicky\" = ? " +
"AND i.\"Pocet posteli\" >= ? " +
"AND p.\"Cena pobytu\" <= ? ";
//"AND p.\"Datum od\" = ? " +
//"AND p.\"Datum do\" <= ?";
int i = 1;
PreparedStatement pst = con.prepareStatement(query, ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
pst.setFetchSize(50);
pst.setString(1,Text_nazov.getText());
pst.setString(2,(String)krajina.getValue());
int pocet_hviezdiciek = Integer.parseInt((String)hviezdicky.getValue());
pst.setInt(3,pocet_hviezdiciek);
int pocet_osob = Integer.parseInt((String)osoby.getValue());
pst.setInt(4, pocet_osob);
double cena_pobytu = Double.parseDouble(Text_cena.getText());
pst.setDouble(5, cena_pobytu);
// Date datum_OD = Date.valueOf(date_od.getValue());
// pst.setDate(6, datum_OD);
// Date datum_DO = Date.valueOf(date_do.getValue());
// pst.setDate(7, datum_DO);
ResultSet rs = pst.executeQuery();
System.out.println(pst);
Nazov_hotela.setCellValueFactory(new PropertyValueFactory<>("Meno_hotela"));
Krajina.setCellValueFactory(new PropertyValueFactory<>("Krajina"));
Mesto.setCellValueFactory(new PropertyValueFactory<>("Mesto"));
Adresa.setCellValueFactory(new PropertyValueFactory<>("Adresa"));
Hviezdicky.setCellValueFactory(new PropertyValueFactory<>("Hviezdicky"));
Cena.setCellValueFactory(new PropertyValueFactory<>("Cena"));
Typ_izby.setCellValueFactory(new PropertyValueFactory<>("Typ_izby"));
Pocet_izieb.setCellValueFactory(new PropertyValueFactory<>("Pocet_izieb"));
while(rs.next()){
oblist.add(new Vysledok_hladania(rs.getString("Nazov hotela"),
rs.getString("Nazov krajiny"),
rs.getString("Nazov mesta"),
rs.getString("Adresa hotela"),
rs.getInt("Hviezdicky"),
rs.getDouble("Cena pobytu"),
rs.getString("Typ izby"),
rs.getInt("Pocet izieb")));
System.out.println(i++);
}
rs.close();
pst.close();
con.close();
} catch(SQLException ex){
Logger.getLogger(Result_Controller.class.getName()).log(Level.SEVERE, null, ex);
}
table.setItems(oblist);
}

Related

How to get data from an ArrayList <List> in another class?

I'm using RecyclerView I have an Activity that queries my database and I insert this data into that ArrayList , and I want to list that data in another Activity.
This is where I query and add the data to the ArrayList
String queryProduto = "SELECT" +
" Produto_Servico.ID, Produto_Servico.Descricao," +
" Produto_Estoque.EstoqueAtual, ValorVenda" +
" FROM" +
" Produto_Valor" +
" INNER JOIN" +
" Produto_Servico" +
" ON" +
" Produto_Servico.ID = Produto_Valor.ID_Produto" +
" INNER JOIN" +
" Produto_Estoque" +
" ON" +
" Produto_Estoque.ID_Produto = Produto_Servico.ID" +
" WHERE" +
" Produto_Estoque.EstoqueAtual > 0" +
" ORDER BY" +
" Produto_Servico.Descricao";
Statement stmtP = connect.createStatement();
ResultSet rsP = stmtP.executeQuery(queryProduto);
String queryPessoa = "SELECT ID_Pessoa FROM Novo_Pedido";
Statement stmtPS = connect.createStatement();
ResultSet rsPS = stmtPS.executeQuery(queryPessoa);
while (rsPS.next()){
cod = rsPS.getString("ID_Pessoa");
}
if (rsP != null) {
while (rsP.next()) {
id = String.valueOf(rsP.getString("ID"));
desc = rsP.getString("Descricao");
estoque = String.valueOf(rsP.getString("EstoqueAtual"));
valorDec = rsP.getBigDecimal(4);
qtdStr = String.valueOf(qtd);
valorStr = decimalFormat.format(valorDec);
String descFinal = desc;
String qtdFinal = qtdStr;
final BigDecimal[] valorFinal = {valorDec};
try {
listProdutosPedidosFinalizar.add(new ListProdutosPedidosFinalizar(descFinal, qtdFinal, valorFinal[0], BigDecimal.ZERO));
classeLists.setListProdutosPedidosFinalizar(listProdutosPedidosFinalizar);
produtosPedidosAdapter = new ProdutosPedidosAdapter(listProdutosPedidos, this, new ProdutosPedidosAdapter.OnClickListener() {
/*METHODS*/
produtosPedidosAdapter.notifyDataSetChanged();
listProdutosPedidos.add(new ListProdutosPedidos(id, desc, estoque, valorStr, qtdStr));
} catch (Exception ex) {
ex.printStackTrace();
}
rvProdutosPedidos.setAdapter(produtosPedidosAdapter);
produtosPedidosAdapter.notifyDataSetChanged();
isSuccess = true;
}
And now I want to list the listProdutosPedidos data in another Activity.
Define listProdutosPedidos list as static member of your class and then use className.listProdutosPedidos code to access records in it.

JTable has size limitations?

the table only displays 3083 line while in mysql are more than that !
DefaultTableModel modelEtud = new DefaultTableModel(null, new String[]{"N°", "C.I.N. / N° inscription", "Nom Fr", "Prenon Fr", "Matière", "Nombre Absences", "Groupe"}) {
};
String requetEtud = "SELECT * FROM etudiant2sga WHERE id = '" + resultatAbs.getString("idEtudiant") + "' AND idGroupe = '" + idGroupe + "' LIMIT 0 , 10000";
try {
ResultSet resultat = stmtSelectEtudiant.executeQuery(requetEtud);
while (resultat.next()) {
modelEtud.addRow(new Object[]{N, resultat.getString("id"), resultat.getString("nomFr"), resultat.getString("prenomFr"), EE, new SimpleDateFormat("dd-MM-yyyy").format(resultatAbs.getDate("dateAbs")), "séance " + resultatAbs.getInt("seance"), jTableGpr.getValueAt(row, 2)});
}
}
even with this code the problem is not solved:
modelEtud.setRowCount(10000);

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 "

Java MySQL returns only one row

I have this code:
try {
Integer user = InformationService.authenticate(username, password, connection);
Statement st = connection.createStatement();
ResultSet rs = st.executeQuery("SELECT * FROM tasks WHERE uid = " + user + " ORDER BY title ASC");
System.out.println("SELECT * FROM tasks WHERE uid = " + user + " ORDER BY title ASC");
while (rs.next()) {
Task p = new Task(rs.getString("title"), rs.getInt("id"), rs.getString("descriere"),
rs.getString("data"), rs.getInt("uid"), rs.getString("data_creare"), rs.getString("ora"),
rs.getInt("status"), rs.getString("priority"), rs.getInt("sters"), rs.getInt("id_parinte"),
rs.getInt("notify"), rs.getString("assigner"), rs.getInt("durata"), rs.getInt("project_id"));
System.out.println(p);
tasks.add(p);
}
The problem is that it returns only the first row, and if I run the query manually I get more results (16 total). Here's the output:
SELECT * FROM tasks WHERE uid = 4 ORDER BY title ASC
models.Task#164b9b8f
Any idea why this is happening?
May be you can improve the code a bit like below which will help you to quickly identify the issue.
int rowCount = 0;
try {
Integer user = InformationService.authenticate(username, password, connection);
Statement st = connection.createStatement();
String query = "SELECT * FROM tasks WHERE uid = " + user + " ORDER BY title ASC";
System.out.println(query);
ResultSet rs = st.executeQuery(query);
while (rs.next()) {
Task p = new Task(rs.getString("title"), rs.getInt("id"), rs.getString("descriere"),
rs.getString("data"), rs.getInt("uid"), rs.getString("data_creare"), rs.getString("ora"),
rs.getInt("status"), rs.getString("priority"), rs.getInt("sters"), rs.getInt("id_parinte"),
rs.getInt("notify"), rs.getString("assigner"), rs.getInt("durata"), rs.getInt("project_id"));
rowCount++;
System.out.println(rowCount + "." + p);
tasks.add(p);
}
} finally {
System.out.println("Number of records = " + rowCount);
}
In this approach you can clearly identify how many rows were iterated.

MYSQL LIMIT not working as expected - Java

I have this weird problem in java when trying to fetch records from MYSql database by using the limit function in the query. Not sure what went wrong or did wrong, this query is giving me a hard time.
Issue - When I run this query through my java program it returns all the records and not limiting the records to 10 as given in the limit.
The same query when ran in MYSql command line, it execute very well and fetches me only 10 recrods.
Below is the java code and query. Any help or support is appreciated.!
Java code -
public UserVO getApplUserDetailsList(UserVO userVO) throws CAPDAOException {
List<UserVO> returnList = null;
String methodName = "getApplUserDetails()";
Session session = null;
String queryString = null;
Transaction transaction = null;
PreparedStatement ps = null;
ResultSet rs = null;
if(userVO == null)
{
logger.writeToTivoliAlertLog(className, CAPConstants.ERROR, methodName, null, "userVO returned null. Busines validation error.!", null);
throw new CAPDAOException("userVO returned null. Busines validation error.!",CAPException.BUSINESS_VALIDATION_ERROR_SECURITY);
}
try {
returnList = new ArrayList<UserVO>();
System.out.println("");
String appusr = userVO.getAppUsrNm();
session = getSession();
transaction = session.beginTransaction();
if(userVO.getAppUsrRoleCd()!=null && !userVO.getAppUsrRoleCd().trim().equalsIgnoreCase(CAPConstants.DEFAULT_DROPDOWN_VALUE)){
queryString = "SELECT " +
"APPL_USR_ID,APPL_USR_NM,APPL_USR_FRST_NM, " +
"APPL_USR_LST_NM,ACCESS_ROLE_CD " +
"FROM APPL_USR " +
"WHERE " +
"APPL_USR_NM LIKE ?"+
" AND APPL_USR_FRST_NM LIKE ?"+
" AND APPL_USR_LST_NM LIKE ?"+
" AND ACCESS_ROLE_CD = ?"+
" AND APPL_USR_ID != ?";
ps = session.connection().prepareStatement(queryString);
ps.setString(1,userVO.getAppUsrNm()+CAPConstants.PERCENTILE_SYMBOL);
ps.setString(2,userVO.getAppUsrFirstNm()+CAPConstants.PERCENTILE_SYMBOL);
ps.setString(3,userVO.getAppUsrLastNm()+CAPConstants.PERCENTILE_SYMBOL);
ps.setString(4,userVO.getAppUsrRoleCd());
ps.setInt(5, 1);
}
else
{
queryString = "SELECT " +
"APPL_USR_ID,APPL_USR_NM,APPL_USR_FRST_NM, " +
"APPL_USR_LST_NM,ACCESS_ROLE_CD " +
"FROM APPL_USR " +
"WHERE " +
"APPL_USR_NM LIKE ?"+
" AND APPL_USR_FRST_NM LIKE ?"+
" AND APPL_USR_LST_NM LIKE ?"+
" AND APPL_USR_ID != ?";
ps = session.connection().prepareStatement(queryString);
ps.setString(1,userVO.getAppUsrNm()+CAPConstants.PERCENTILE_SYMBOL);
ps.setString(2,userVO.getAppUsrFirstNm()+CAPConstants.PERCENTILE_SYMBOL);
ps.setString(3,userVO.getAppUsrLastNm()+CAPConstants.PERCENTILE_SYMBOL);
ps.setInt(4, 1);
}
if(userVO.getQueryAction()!=null && userVO.getQueryAction().equals(CAPConstants.GET_DATA))
queryString += " ORDER BY APPL_USR_ID LIMIT " + userVO.getPAGE_MIN_LIMIT() + ", " + userVO.getPAGE_MAX_LIMIT();
else
queryString += " ORDER BY APPL_USR_ID";
rs = ps.executeQuery();
if(userVO.getQueryAction()!=null && userVO.getQueryAction().equals(CAPConstants.GET_DATA))
{
int tempCOunt = 0;
while(rs!=null && rs.next())
{
tempCOunt ++;
UserVO returnVO = new UserVO();
returnVO.setAppUsrId(rs.getInt("APPL_USR_ID"));
returnVO.setAppUsrNm(rs.getString("APPL_USR_NM"));
returnVO.setAppUsrFirstNm(rs.getString("APPL_USR_FRST_NM"));
returnVO.setAppUsrLastNm(rs.getString("APPL_USR_LST_NM"));
if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.ADMINISTRATOR_ROLE_CD))
returnVO.setApplicationLevelRole("Administrator");
else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.MAINTAINER_ROLE_CD))
returnVO.setApplicationLevelRole("Maintainer");
else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.VIEWER_ROLE_CD))
returnVO.setApplicationLevelRole("Viewer");
else
returnVO.setApplicationLevelRole("None");
returnList.add(returnVO);
}
System.out.println("Count >>>>>>>>>>>>>>>>>>> "+tempCOunt);
userVO.setReturnListFromDB(returnList);
}
else
{
int rowcount = 0;
if (rs.last()) {
rowcount = rs.getRow();
rs.beforeFirst(); // not rs.first() because the rs.next() below will move on, missing the first element
}
userVO.setTotalRecordCount(rowcount);
System.out.println("Total count of the records to be used for pagination >> "+rowcount);
rowcount = 0;
while(rs!=null && rs.next())
{
rowcount ++;
UserVO returnVO = new UserVO();
returnVO.setAppUsrId(rs.getInt("APPL_USR_ID"));
returnVO.setAppUsrNm(rs.getString("APPL_USR_NM"));
returnVO.setAppUsrFirstNm(rs.getString("APPL_USR_FRST_NM"));
returnVO.setAppUsrLastNm(rs.getString("APPL_USR_LST_NM"));
if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.ADMINISTRATOR_ROLE_CD))
returnVO.setApplicationLevelRole("Administrator");
else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.MAINTAINER_ROLE_CD))
returnVO.setApplicationLevelRole("Maintainer");
else if (rs.getString("ACCESS_ROLE_CD")!=null && rs.getString("ACCESS_ROLE_CD").trim().equalsIgnoreCase(CAPConstants.VIEWER_ROLE_CD))
returnVO.setApplicationLevelRole("Viewer");
else
returnVO.setApplicationLevelRole("None");
returnList.add(returnVO);
System.out.println("Row count >>"+rowcount);
if(rowcount == CAPConstants.PAGINATION_MAX_VALUE)
break;
}
rowcount = 0;
userVO.setReturnListFromDB(returnList);
}
System.out.println("returnList >>"+returnList);
return userVO;
} catch (Throwable e) {
e.printStackTrace();
logger.writeToTivoliAlertLog(className, CAPConstants.ERROR, methodName, userVO.getAppUsrNm(), "Error occured while trying to fetch application user details. Printing stack trace to the log for analysis..", e);
throw new CAPDAOException("Error occured while trying to fetch application user details.",CAPException.SPEXECUTION_ERROR_CODE);
}
finally{
closeTransactionAndSession(session,transaction);
}
}
MYSQL Query -
SELECT APPL_USR_ID,APPL_USR_NM,APPL_USR_FRST_NM, APPL_USR_LST_NM,ACCESS_ROLE_CD
FROM APPL_USR WHERE APPL_USR_NM LIKE '%'
AND APPL_USR_FRST_NM LIKE '%'
AND APPL_USR_LST_NM LIKE '%'
AND APPL_USR_ID != 1
ORDER BY APPL_USR_ID
LIMIT 10, 10
you add your LIMIT after
ps = session.connection().prepareStatement(queryString);
so when calling
rs = ps.executeQuery();
the LIMIT is not in there.
So, call prepareStatement when the queryString construction is finished.
You are changing the querystring after you have prepared the statement with the string.

Categories

Resources