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Update data in table

The thing i want to achieve here is that i have a table name total_product in mysql database and i want to retrieve the value of SNo = 1 from the table and update the Quantity in the table.
There is a text box i am using in GUI in which the additional product produced will be written.
The output from the table is stored in variable id and the new quantity that is produced is stored in the variable q1.
so the new product quantity will be q1 = q1 + id.
I am not able to understand what should i put in the sql statement that is used in stmt.executeUpdate(sql) because the sql is a string and i have to pass an integer value to Qunty in the sql string.
Please Help.
Connection conn = null ;
Statement stmt = null ;
String url = "jdbc:mysql://localhost:3306/project";
String user = "root";
String password = ".dpadpep";
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(url,user,password);
String sql = "Select Qunty from total_product " + "where SNo = 1";
stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(sql);
int id=0;
int q1 = Integer.parseInt(fld1[0].getText());
while(rs.next()) {
id = rs.getInt(1);
System.out.println("Quantity="+id);
}
q1 = q1+id;
sql = "UPDATE total_product " + "set Qunty = q1 where SNo=1";
stmt.executeUpdate(sql);

You don't need to explicitly retrieve the current value in the database, you can simply add the additional amount directly:
int q1 = Integer.parseInt(fld1[0].getText());
String sql = "UPDATE total_product SET Qunty = Qunty + ? WHERE SNo = 1";
PreparedStatement ps = conn.prepareStatement(sql);
ps.setInt(1, q1);
ps.executeUpdate();

Batch Execute as Aysnc Does not update any row

I am trying to use aync update of dsc cassandra 3,
Integer count = 0;
String query = "select status, guid from catalog_new where affiliate_id = ? AND store_id =?";
String approveStoreQuery = "UPDATE catalog_new SET status = ? WHERE affiliate_id = ? AND store_id = ? AND guid = ?";
PreparedStatement selectStmt = session.prepare(query);
BoundStatement selectBoundStatement = new BoundStatement(selectStmt);
ResultSet selectSet = session.execute(selectBoundStatement.bind(new Object[]{affiliateId, storeId}));
BatchStatement batchStatement = new BatchStatement(BatchStatement.Type.UNLOGGED);
Iterator<Row> rowItr = selectSet.iterator();
while (!selectSet.isFullyFetched()) {
selectSet.fetchMoreResults();
Row row = rowItr.next();
if(row.getInt("status") == statusFrom){
String guid = row.getString("guid");
PreparedStatement preparedStatement = session.prepare(approveStoreQuery);
BoundStatement boundStatement = new BoundStatement(preparedStatement);
batchStatement.add(boundStatement.bind(new Object[]{statusTo, affiliateId, storeId, guid}));
count++;
}
}
session.executeAsync(batchStatement);
return count;
{Here statusFrom is -2 and statusto is -2 , ids are 3 and 9}
This does not update any row, what I am doing wrong here?

I found it:
Just replace the while construct with a do while and you will be fine!
I also tested this code against select fetch statement that has multiple pages, so it should work as expected for you:
import com.datastax.driver.core.*;
import java.util.Iterator;
public class Hello {
public static void main(String[] args) {
Cluster cluster = Cluster.builder()
.addContactPoint("127.0.0.2")
.build();
//I tried to reverse engineer this from your code:
//I think it's relatively close to what you got
/*
CREATE TABLE catalog_new (
affiliate_id text,
store_id text,
guid text,
status int,
PRIMARY KEY(affiliate_id, store_id, guid)
);
-- Just some test data
INSERT INTO catalog_new(affiliate_id, store_id, guid, status) VALUES ('af1', 'st1', 'guid1', 0);
INSERT INTO catalog_new(affiliate_id, store_id, guid, status) VALUES ('af1', 'st1', 'guid2', 0);
INSERT INTO catalog_new(affiliate_id, store_id, guid, status) VALUES ('af1', 'st1', 'guid3', 0);
*/
Session session = cluster.connect();
String affiliateId = "af1";
String storeId = "st1";
Integer statusFrom = 0;
Integer statusTo = 1;
Integer count = 0;
String query = "select status, guid from test.catalog_new where affiliate_id = ? AND store_id =?";
String approveStoreQuery = "UPDATE test.catalog_new SET status = ? WHERE affiliate_id = ? AND store_id = ? AND guid = ?";
PreparedStatement selectStmt = session.prepare(query);
BoundStatement selectBoundStatement = new BoundStatement(selectStmt);
ResultSet selectSet = session.execute(selectBoundStatement.bind(new Object[]{affiliateId, storeId}));
Iterator<Row> rowItr = selectSet.iterator();
BatchStatement batchStatement = new BatchStatement(BatchStatement.Type.UNLOGGED);
// the way you wrote it is
// while (!selectSet.isFullyFetched()) {
// basically you never even go into a loop
// you might try a do while! - that's all there is to it
do {
selectSet.fetchMoreResults();
Row row = rowItr.next();
if (row.getInt("status") == statusFrom) {
String guid = row.getString("guid");
PreparedStatement preparedStatement = session.prepare(approveStoreQuery);
BoundStatement boundStatement = new BoundStatement(preparedStatement);
batchStatement.add(boundStatement.bind(statusTo, affiliateId, storeId, guid));
count++;
}
} while (!selectSet.isFullyFetched());
session.executeAsync(batchStatement);
// I just made simple print without returning anything just to make sure this works, I tried your example locally and everything runs fine
System.out.println(count);
}
}

`createSQLException` when trying to get all rows in MySQL table

I have a simple table consisting of 4 strings and 2 integers (of which one is an ID).
I use a special function to get all rows inside that table:
public Booking[] displayAllBookings() throws ClassNotFoundException, SQLException{
Connection con = connect.getConnection();
PreparedStatement counter = (PreparedStatement) con.prepareStatement("select count(*) from bookings");
ResultSet count = counter.executeQuery();
Booking[] array = new Booking[count.getInt(1)];
String name = null,surname = null,begindate = null,enddate = null;
int persons = 0,i=0;
PreparedStatement posted = (PreparedStatement) con.prepareStatement("SELECT * FROM bookings");
result = posted.executeQuery();
while (result.next()){
begindate = result.getString("begindate");
enddate = result.getString("enddate");
name = result.getString("Name");
surname = result.getString("Surname");
persons = result.getInt("persons");
Booking temp = new Booking(begindate,enddate,name,surname,persons);
array[i++]=temp;
}
return array;
}
But when I execute it I get this exception:
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:897)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:886)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860)
at com.mysql.jdbc.ResultSetImpl.checkRowPos(ResultSetImpl.java:790)
at com.mysql.jdbc.ResultSetImpl.getInt(ResultSetImpl.java:2472)
at DataBase.DataCommunicatorBooking.displayAllBookings(DataCommunicatorBooking.java:59)
at DataBase.main.displayAll(main.java:125)
at DataBase.main.main(main.java:71)
I've tried looking up this exception but I can't find anything that corresponds to my problem.

You are trying to get the value of the column maxPersons which is not even defined in the table... you meant for sure persons
name = result.getString("Name");
maxPersons = result.getInt("persons");
Room temp = new Room(name,maxPersons);

The problem was with the
PreparedStatement counter = (PreparedStatement) con.prepareStatement("select count(*) from bookings");
ResultSet count = counter.executeQuery();
so I used an ArrayList like so:
public Booking[] displayAllBookings() throws ClassNotFoundException, SQLException{
Connection con = connect.getConnection();
ArrayList<Booking> bookings = new ArrayList<Booking>();
String name = null,surname = null,begindate = null,enddate = null;
int persons = 0,i=0;
PreparedStatement posted = (PreparedStatement) con.prepareStatement("SELECT * FROM bookings");
result = posted.executeQuery();
while (result.next()){
begindate = result.getString("begindate");
enddate = result.getString("enddate");
name = result.getString("Name");
surname = result.getString("Surname");
persons = result.getInt("persons");
Booking temp = new Booking(begindate,enddate,name,surname,persons);
bookings.add(temp);
}
return bookings.toArray(new Booking[bookings.size()]);
}
and that solved the problem;

This is because the column "maxPersons" does not exist, you probably ment "persons"

Inserting Data into Sql Using Java Netbeans

I want to insert input given by user into Sql Table using Java, but dont know how many coloumn is need.
eg.
insert into table_name values('"+id+"','"+name+"')
this query is not going to work because I don't know the column name i.e ID, name.
I want the query that is universal for any inserting data.

As per my need I tried this code. I HOPE IT WORKED FOR ALL.
void getTableInput(String tname, String dname) throws ClassNotFoundException, SQLException {
this.tname = tname;
this.dname = dname;
Scanner s = new Scanner(System.in);
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
String conURL = "jdbc:sqlserver://localhost:1433;databaseName=" + this.dname + ";user=JT_DATA;password=1234";
Connection con = DriverManager.getConnection(conURL);
Statement st = con.createStatement();
ResultSet rs = st.executeQuery("SELECT * FROM " + this.tname);
ResultSetMetaData rsmd = rs.getMetaData();
int colNo = rsmd.getColumnCount();
String colName[] = new String[colNo];
String[] get_User_Input = new String[100];
for (int i = 1; i <=colNo; i++)
{
colName[i-1] = rsmd.getColumnLabel(i);
System.out.print(Arrays.toString(colName) + " : ");
get_User_Input[i-1] = s.next();
}
String store="";
for(int i=0;i<colNo;i++)
{
store += "'"+get_User_Input[i]+"',";
}
store = store.substring(0,store.length() -1);
PreparedStatement pst = con.prepareStatement("insert into "+this.tname+" values ("+ store +")");
pst.executeUpdate();
System.out.println("Data Inserted");
}
But the problem with this is that. This can only insert String Datatype.

I dont think there is any universal query.
If you dont know column name than you can find name of the column by using meta data.
You can get meta data of the connections (database)
DatabaseMetaData databaseMetaData = connection.getMetaData();
You can also get list of the tables.
String catalog = null;
String schemaPattern = null;
String tableNamePattern = null;
String[] types = null;
ResultSet result = databaseMetaData.getTables(
catalog, schemaPattern, tableNamePattern, types );
while(result.next()) {
String tableName = result.getString(3);
}
Listing column name in table.
String catalog = null;
String schemaPattern = null;
String tableNamePattern = "my_table";
String columnNamePattern = null;
ResultSet result = databaseMetaData.getColumns(
catalog, schemaPattern, tableNamePattern, columnNamePattern);
while(result.next()){
String columnName = result.getString(4);
int columnType = result.getInt(5);
}
In this way you can find column name and can create query dynamically.

How to get a particular column's values alone?

I am using the mysql java connector. I need java to display the contents of the first column and the second column in different steps. How do I achieve this?
String qry = "select col1,col2 from table1";
Resultset rs = statement.executeQuery(qry);

I've posted a sample below:
Statement s = conn.createStatement ();
s.executeQuery ("SELECT id, name, category FROM animal");
ResultSet rs = s.getResultSet ();
int count = 0;
while (rs.next ())
{
int idVal = rs.getInt ("id");
String nameVal = rs.getString ("name");
String catVal = rs.getString ("category");
System.out.println (
"id = " + idVal
+ ", name = " + nameVal
+ ", category = " + catVal);
++count;
}
rs.close ();
s.close ();
System.out.println (count + " rows were retrieved");
(From: http://www.kitebird.com/articles/jdbc.html#TOC_5 )
Edit: just re-read the question and think you might mean you want to refer to a column later on in code, instead of in the inital loop as in my example above. In that case, you can create an array and refer to the array later on, or, as another answer suggests you can just do another query.

Load them into any data structure of your choice and then display them to your heart's content.
List<String> firstCol = new ArrayList<String>();
List<String> secondCol = new ArrayList<String>();
while(rs.next()){
firstCol.add(rs.getString("col1"));
secondCol.add(rs.getString("col2"));
}
Then you can manipulate with the two list as you want.

How about ... (insert drumroll here):
String qry1 = "select col1 from table1";
Resultset rs1 = statement.executeQuery(qry);
String qry2 = "select col2 from table1";
Resultset rs2 = statement.executeQuery(qry);
(You might want to phrase your question more clearly.)

You can do it like this :
String sql = "select col1,col2 from table1";
ResultSet rs = stmt.executeQuery(sql);
while (rs.next()) System.out.println(rs.getString("col1"));

I am using following Code:
Statement sta;
ResultSet rs;
try {
sta = con.createStatement();
rs = sta.executeQuery("SELECT * FROM TABLENAME");
while(rs.next())
{
Id = rs.getString("COLUMN_Name1");
Vid = rs.getString("COLUMN_Name2");
System.out.println("\n ID : " + Id);
System.out.println("\n VehicleID: " + Vid);
}
}
catch(Execption e)
{
}
And this code is 100% working.

String emailid=request.getParameter("email");
System.out.println(emailid);
rt=st.executeQuery("SELECT imgname FROM selection WHERE email='emailid'");
System.out.println(rt.getString("imgname"));
while(rt.next())
{
System.out.println(rt.getString("imgname"));
finalimage=rt.getString("imgname");
}