ResultSet next() is returning only one row - jdbc

I am having this method
public List<Course> getCourses() throws InvalidCourseDataException {
ArrayList<Course> allCoursesFromDB = new ArrayList<>();
Connection dbConnection = null;
String getFromTableSQL = "SELECT * FROM courses";
try {
dbConnection = getDBConnection();
statement = dbConnection.createStatement();
resultSet = statement.executeQuery(getFromTableSQL);
while (resultSet.next()) {
String courseCategory = resultSet.getString("course_category");
String courseTitle = resultSet.getString("course_title");
int courseId = resultSet.getInt("course_id");
Date startDate = resultSet.getTimestamp("starting_date");
Date endDate = resultSet.getDate("ending_date");
String description = resultSet.getString("description");
int teacherId = resultSet.getInt("teacher_id");
Course course = new Course(courseCategory, courseTitle, startDate, endDate);
course.setCourseId(courseId);
course.setTeacherId(teacherId);
course.setDescription(description);
addParticipantsIdToCourse(course);
allCoursesFromDB.add(course);
}
The getDBConnection() method is
private static Connection getDBConnection() {
System.out.println("-------- MySQL JDBC Connection Testing ------------");
Connection dbConnection = null;
try {
Class.forName(DB_DRIVER);
} catch (ClassNotFoundException e) {
System.out.println(e.getMessage());
}
try {
dbConnection = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD);
return dbConnection;
} catch (SQLException e) {
System.out.println(e.getMessage());
}
return dbConnection;
}
My problem is that resultSet.next() is returning only the first row from DB. I'am sure that I have multiple rows. I saw JDBC ResultSet is giving only one row although there are many rows in table? that question but it really doesn't answer my :)

I am sorry for the question. I found my mistake. ResultSet next() method is working fine, but I've changed its value in my addParticipantsIdToCourse(course) method :)

Related

call an oracle function with array as parameter via hibernate

So i hava an oracle functiion like: function unbind (ids in id_table). It takes an array of ids to perform some updates on my database.
The question is how can I run my function in order to perform update operations?
What I've alreade tried:
1. Query query = getSession().createSQLQuery("call UNBIND(:ids)");
query.setParameter("ids", myIds);
query.executeUpdate();
but I got ora-06576 not a valid function or procedure name
Query query = getSession().createSQLQuery("execute UNBIND(:ids)");
query.setParameter("ids", myIds);
query.executeUpdate();
finish with ora-00900 invalid sql statement
Long [] myArray = movedIds.toArray(new Long[movedIds.size()]);
Boolean result = getSession().doReturningWork(new ReturningWork<Boolean>() {
#Override
public Boolean execute(Connection connection) throws SQLException {
CallableStatement callableStatement = connection.prepareCall("{ ? = call UNBIND(:ids)");
callableStatement.registerOutParameter(1, Types.INTEGER);
callableStatement.setArray(2, connection.createArrayOf("id_table", myArray));
callableStatement.execute();
return !(callableStatement.getInt(1) == 0);
}
});
finishes with java.sql.sqlfeaturenotsupportedexception unsupported feature
The app conects to the database via jboss, so I suppose that could be the problem in p. 3?
SELECT
UNBIND( id_table (6271789) ) FROM DUAL
does not work because my function performs updates...
Anyway is there any other method to run a function that takes an array as a parameter directly from java code?
here is a simple example, does this help?
import java.sql.*;
public class Class1 {
public static void main(String[] args) throws SQLException {
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Connection conn = null;
try {
conn = DriverManager.getConnection(
"jdbc:oracle:thin:#//localhost/orcl","scott","tiger");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String query = "{ ? = call test_func(?) }";
CallableStatement cs = null;
try {
cs = conn.prepareCall(query);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
int inVal = 0;
cs.setInt(2, inVal);
cs.registerOutParameter(1, oracle.jdbc.OracleTypes.NUMBER);
cs.executeUpdate();
int res = cs.getInt(1);
System.out.println("result is " + res);
}
}

Is it a good programming to pass Connection Object to a method?

I am doing a Insert Operation , i have a condition if company is 0 , then i need to perform an additional insert in another table ??
This is my code
public static String insertIntoDepotTable(DepotJSONBean depotbean) throws SQLException
{
Connection dbConnection = null;
PreparedStatement depotjsoninsertPst = null ;
try
{
dbConnection = DBConnectionOrientDepot.getDBConnection();
dbConnection.setAutoCommit(false);
String companyId = depotbean.getCompanyId();
if(companyId.equals("0"))
{
saveInCompany(depotbean , dbConnection);
}
String Insertsql = "INSERT INTO tbl_depot values (depotID,depoBelongsToID,stateID,districtID,talukMandalID,depotName,companyID,contactName,phone1,phone2,address,latitude,longititude,accuracy,town,noOfPeopleOperating,depotSize,storageCapacity,cAndFNames,depotPic1,depotPic2,comments,active,createdOn,modifiedOn) VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)";
depotjsoninsertPst = dbConnection.prepareStatement(Insertsql);
}
catch(Exception e)
{
}
} // end of method
public String saveInCompany(DepotJSONBean djsonbean , Connection conn)
{
}

How to Connect oracle db with JSP

I am a new for JSP and I dont know any information about connection of oracle with JSP can anyone help me step by step?
You have to look at JDBC for Oracle. Using Java of course, not JSP.
This is a very basic Database class I used to use for very little projects.
public class Database {
private String driverName = "oracle.jdbc.driver.OracleDriver";
private Connection conn;
public static Hashtable errors = null;
public Database(String serverName, String portNumber, String serviceName, String username, String password, String db) {
errors = new Hashtable();
try {
String url = "jdbc:oracle:thin:#" + serverName + ":" + portNumber + ":" + serviceName;
Class.forName(driverName);
this.conn = DriverManager.getConnection(url, username, password);
} catch (Exception e) {
System.out.println(e);
errors.put(db, e);
}
}
public Connection getConnection(){
return this.conn;
}
}
here is a sample of a query
Database db = new Database(......); // see Database class construct
try {
java.sql.Statement st = db.getConnection().createStatement();
ResultSet rs = st.executeQuery("SELECT * FROM FOO");
while(rs.next()){
// your code
}
rs.close();
st.close();
} catch (SQLException ex) {
Logger.getLogger(Table.class.getName()).log(Level.SEVERE, null, ex);
}
hope this helps :)

Doesn't match table_names jdbc program showing result and sql showing result

My jdbc program code
package table;
import java.sql.*;
public class sdfjksjk {
static final String JDBC_DRIVER = "oracle.jdbc.driver.OracleDriver";
static final String DB_URL = "jdbc:oracle:thin:#192.168.1.12:1521:aftdb";
static final String USER = "system";
static final String PASS = "manager";
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
try{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Connecting to database...");
conn = DriverManager.getConnection(DB_URL,USER,PASS);
System.out.println("Creating statement...");
stmt = conn.createStatement();
String sql;
DatabaseMetaData md = conn.getMetaData();
ResultSet rs = md.
getTables(null, "SYSTEM", "%", null);
while (rs.next())
{
System.out.println(rs.getString(3));
}
rs.close();
stmt.close();
conn.close();
}catch(SQLException se){
se.printStackTrace();
}catch(Exception e){
e.printStackTrace();
}finally{
try{
if(stmt!=null)
stmt.close();
}catch(SQLException se2){
}
try{
if(conn!=null)
conn.close();
}catch(SQLException se){
se.printStackTrace();
}
}
}
}
this code showing 231 table name,but in my sql developer select table_name from user_tables it showing 207 table names. What is the wrong in my program?
The last parameter of md.getTables is a list of table types.
You supply the value null which lists all table types ("TABLE", "VIEW" and possibly other types).
In sql developer you are just seeing regular tables (not views).
Edit:
Make the call like this to just get regular tables:
String regularTables[] = new String[] {"TABLE"};
ResultSet rs = md.
getTables(null, "SYSTEM", "%", regularTables);

How do I display arrayList contents from resultset in Java JDBC?

So I am making a simple java project to play around with JDBC in glassfish and see how it works. The program just shows you a list of surveys and a list of questions for the survey you select. However i cant seem to display the list of questions for the survey I selected. I keep getting empty values. These are the methods I have created:
convert the resultset to object model data values
public JHAKSurvey findSurvey(long id) {
System.out.println("JDBC: FIND SURVEY");
Connection connection = null;
PreparedStatement ps = null;
ResultSet rs = null;
JHAKSurvey survey = null;
try {
connection = openConnection();
String query = "SELECT * FROM APP.SURVEY WHERE ID=?";
ps = connection.prepareStatement(query);
ps.setLong(1, id);
rs = ps.executeQuery();
while (rs.next()) {
survey = createSurveyFromResultSet(rs);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
closeConnection(connection);
}
return survey;
}
private method to query the list of questions from the QUESTION table for a survey id
private void findQuestionsBySurvey(JHAKSurvey survey){
System.out.println("JDBC: FIND QUESTIONS BY SURVEY");
Connection connection = null;
PreparedStatement ps = null;
try {
connection = openConnection();
String query = "SELECT * FROM APP.QUESTION WHERE SURVEYID=?";
ps = connection.prepareStatement(query);
ps.setLong(1, survey.getId());
ps.executeQuery(query);
} catch (Exception e) {
e.printStackTrace();
} finally {
closeConnection(connection);
}
}
private method to convert the find the resultset list to an question object and add it to the survey object
private void createQuestionFromResultSet(ResultSet rs, JHAKSurvey survey){
ArrayList<JHAKQuestion> qList = new ArrayList<JHAKQuestion>();
JHAKQuestion question = new JHAKQuestion();
JHAKSurvey ss = new JHAKSurvey();
//qList.add(survey.getQuestions());
try {
while (rs.next()) {
//question.setDescription(qList.toString());
question.setId(rs.getLong("ID"));
question.setDescription(rs.getString("DESCRIPTION"));
qList.add(question);
survey.setQuestions(qList);
}
System.out.println("createQuestionFromResultSet : JDBC : successful");
} catch (SQLException e) {
// TODO Auto-generated catch block
System.out.println("createQuestionFromResultSet : JDBC : fail");
e.printStackTrace();
}
}
private method to convert a resultset to an survey object.
private JHAKSurvey createSurveyFromResultSet(ResultSet rs){
JHAKSurvey survey = new JHAKSurvey();
Boolean active = false;
String yes;
try {
yes = rs.getString("ACTIVE");
survey.setId(rs.getLong("ID"));
survey.setTitle(rs.getString("TITLE"));
if (yes.equals(Character.toString('Y'))) {
survey.setActive(true);
} else {
survey.setActive(false);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return survey;
}
What am I missing? I also seem to get error:
cannot convert from void to JHAKQuestion
When I try the method: createQuestionFromResultSet();
Thank You
Look at your method:
private void findQuestionsBySurvey(JHAKSurvey survey){
You want to get the questions of a survey, but the method returns void. Make it return a List<Question>. And in the body of the method, iterate through the resultset, transform each row into a question, add the question to a List<Question>, and return this list.
Or, if the goal of the method is to add questions to the survey passed as argument, then rename the method to
private void addQuestionsToSurvey(JHAKSurvey survey) {
and, inside the method body, call the method createQuestionFromResultSet (which should be named createQuestionsFromResultSetAndAddThemToSurvey), with the resultset and the survey as argument:
private void findQuestionsBySurvey(JHAKSurvey survey){
System.out.println("JDBC: FIND QUESTIONS BY SURVEY");
Connection connection = null;
PreparedStatement ps = null;
try {
connection = openConnection();
String query = "SELECT * FROM APP.QUESTION WHERE SURVEYID=?";
ps = connection.prepareStatement(query);
ps.setLong(1, survey.getId());
ResultSet rs = ps.executeQuery(query);
createQuestionFromResultSet(survey);
} catch (Exception e) {
e.printStackTrace();
} finally {
closeConnection(connection);
}
}

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