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Get PostgreSql table size on disk (byte) in ORMlite

I use ORMLite in a Java application, in order to deal with a PostgreSql DataBase.
I want to get the space on the disc used by a table of DataBase.
It seems that OrmLite doesn't have a specific method to get it, so I tried without success:
final String TABLE_NAME = "a_table_name_of_db";
//1)
String SQL = "SELECT pg_relation_size('" + TABLE_NAME + "');" ;
int result = OGGETTO_DAO.executeRaw(SQL);
//2)
String SQL = "SELECT pg_table_size('" + TABLE_NAME + "');" ;
int result = OGGETTO_DAO.executeRaw(SQL);
//3 - it was just a try...)
SQL = "SELECT pg_table_size('" + TABLE_NAME + "');" ;
GenericRawResults<String> ARRAY = OGGETTO_DAO.queryRaw(SQL);
String result= ARRAY.getFirstResult();
With 1) and 2) I get always -1, with 3) I get a cast exception;
I I use the command 'pg_relation_size' or 'pg_table_size' by command line (linux - by psql prompt), it works properly.
What am I wrong?
Thank you
UPDATE - WORKING SOLUTION:
Now it works! Solution, as per accepted answer below, is:
final String TABLE_NAME = "a_table_name_of_db";
String SQL = "SELECT pg_table_size('" + TABLE_NAME + "');"
final long RESULT = OGGETTO_DAO.queryRawValue(SQL); //in bytes

int result = OGGETTO_DAO.executeRaw(SQL);
Yeah that's not right. Looking at the javadocs for executeRaw(...) they say that it returns the number of rows affected not the result.
SQL = "SELECT pg_table_size('" + TABLE_NAME + "');" ;
GenericRawResults ARRAY = OGGETTO_DAO.queryRaw(SQL);
String result= ARRAY.getFirstResult();
Looking at the javadocs for queryRaw(...), the problem here is it returns a GenericRawResults<String[]> and not <String>. It returns a collection of raw results, each row being represented by a string array. I'm really surprised that your code even compiles.
It should be:
GenericRawResults<String[]> ARRAY = OGGETTO_DAO.queryRaw(SQL);
String result= ARRAY.getFirstResult()[0];
Probably the best way to do this is to use queryRawValue(...) which performs a raw query and returns a single value.
// throws an exception if there are no results or if the first one isn't a number
long size = OGGETTO_DAO.queryRawValue(SQL);

SQL fuzzy search

I have to call SQL database search in my Java program.
The retrieving condition is that user input string partially matches NAME filed and not case sensitive. For example, if user input "joe", students' records with name like "Joea", "Bjoe","JOEED" should be returned.
While I tried to write code as bellow. It doesn't seem to be able to work out.
Can someone tell me why? Thanks.
String fuzzySearch = "UPPER(%" + inputStr + "%)";
String query = "SELECT * FROM student WHERE UPPER(student.name) LIKE ? ";
PreparedStatement prepStatement = con.prepareStatement(query.toString());
prepStatement.setObject(1,fuzzySearch);

As you are using a string bind variable, you are saying
WHERE UPPER(student.name) LIKE 'UPPER(%joe%)'
instead of
WHERE UPPER(student.name) LIKE UPPER('%joe%')
So use
String fuzzySearch = "%" + inputStr + "%";
String query = "SELECT * FROM student WHERE UPPER(student.name) LIKE UPPER(?) ";
PreparedStatement prepStatement = con.prepareStatement(query.toString());
prepStatement.setObject(1,fuzzySearch);
instead.

Retrieve database in java using JTextField to search

So, i would like to retrieve database information where a user will search certain columns using text fields, like this:
column1 find userinput,
column2 find userinput,
column3 find userinput,
The problem im having is the sql statement:
String sql = "select * from table where column = '" + textfield1.getText() + "'";
If textfield1 is empty, it will only retrieve entries that contain nothing.
What im trying to retrieve will have 6 text field, meaning 6 columns in the database. Using java i would need alot of if statements.
Is there any other way to shorten this?
EDIT
-- MORE INFO --
The if statements will start from:
if (!(t1.getText().equals("")) && !(t2.getText().equals("")) && !(t3.getText().equals(""))
&& !(t4.getText().equals("")) && !(t5.getText().equals("")) && (t6.getText().equals("")))
all the way down to
if (t1.getText().equals("") && t2.getText().equals("") && t3.getText().equals("")
&& t4.getText().equals("") && t5.getText().equals("") && t6.getText().equals("")
covering all possible combinations of the 6 input fields, the point of all these statements is to ignore empty text fields but provide the corresponding sql statement.
I don't know how to calculate the possible combinations other than writing them all down(i started, there was too many).

I didn't really understand why those ifs, you should elaborate more your question but i will try to help as i can.
Well, if you want to retrieve everything from the database you could use LIKE:
String sql = "select * from table where column like '%" + textfield1.getText() + "%'";
This way you'll get everything with the containing text, it means, if the field is empty it will bring all results, i guess this is the best way to do, to avoid unnecessa if clauses.
Another thing, to check for empty fields you should use:
t1.getText().trim().isEmpty()
BUT if you let they write white spaces the LIKE won't help you then you need to .trim() all your texts then your white spaces will be ignored.

The following can be formulated much neater, but to make the point:
JTextField ts = new JTextField[6];
Set<String> values = new HashSet<>(); // Removes duplicates too.
for (JTextField t : ts) {
String text = ts.getText().trim();
if (!text.isEmpty()) {
values.add(text);
}
}
// Build the WHERE condition of a PreparedStatement
String condition = "";
for (String value : values) {
condition += condition.isEmpty() ? "WHERE" : " OR";
condition += " column = ?";
}
String sql = "select * from table " + condition;
PreparedStatement stm = connection.prepareStatement(sql);
int index = 1; // SQL counts from 1
for (String value : values) {
stm.setString(index, value);
++index;
}
ResultSet rs = stm.executeQuery();
The usage of a PreparedStatement makes escaping ' (and backslash and such) no longer needed and also prevents SQL injection (see wikipedia).

i have a problem i want to search data based on multiple jtext fields where did i go wrong coz this displays only one row which has the first id
private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
String sql="SELECT Employee.EmpID,Employee.Fname,Employee.Mname,Employee.Sname,Employee.DoB,Employee.Phone,"
+ "Employee.Email,Employee.Nationality,Employee.Desegnition,Employee.NSSF,Employee.WCF,"
+ "Employee.BSalary,Allowance.medical,Allowance.Bonus,Allowance.others,Allowance.tov,Allowance.TA,"
+ "Attendece.Hrs from Employee,Allowance,Attendece WHERE "
+ "Employee.EmpID=Allowance.EmpID and Attendece.EmpID=Allowance.EmpID AND Employee.EmpID=? AND Attendece.Dt=?";
try{
pd=conn.prepareStatement(sql);
pd.setString(1,id.getText());
pd.setString(2,Date1.getText());
r=pd.executeQuery();
//setting the text fields
if(r.next())
{
String a=r.getString("EmpID");
eid.setText(a);
String b=r.getString("Fname");
fname.setText(b);
String c=r.getString("Mname");
mname.setText(c);
String d=r.getString("Sname");
sname.setText(d);
String e=r.getString("DoB");
dob.setText(e);
String f=r.getString("Desegnition");
Des.setText(f);
String g=r.getString("Bsalary");
bsal.setText(g);
String h=r.getString("Phone");
phone.setText(h);
String i=r.getString("Email");
email.setText(i);
String j=r.getString("Nationality");
nationality.setText(j);
String k=r.getString("Desegnition");
Des.setText(k);
String l=r.getString("NSSf");
nssf.setText(l);
String m=r.getString("WCF");
wcf.setText(m);
String n=r.getString("tov");
oh.setText(n);
String o=r.getString("Bonus");
bn.setText(o);
String p=r.getString("medical");
md.setText(p);
String q=r.getString("others");
ot.setText(q);
String s=r.getString("TA");
ta.setText(s);
String t=r.getString("Hrs");
hrs.setText(t);
int day;
day=Integer.parseInt(t)/8;
days.setText(Integer.toString(day));
double week=day/7;
weeks.setText(Double.toString(week));
}
r.close();
pd.close();
}catch(Exception e)
{
}

Error: Before start of result set in Java

I know this would be a foolish question to ask but still i need to do this.
This is a basic program in java application where I want to use 3 queries simultaneously to print the table.
(I'm not using any Primary key in this case so please help me to resolve this without making my attributes as primary keys - I know this is not a good practice but for now i need to complete it.)
my code:
Connection con = null;
Statement stat1 = null, stat2 = null, stat3 = null;
ResultSet rs1, rs2, rs3;
stat1 = con.createStatement();
stat2 = con.createStatement();
stat3 = con.createStatement();
String str = "\nProduct\tC.P\tS.P.\tStock\tExpenditure\tSales";
info.setText(str);
String s1 = "SELECT type, cp, sp, stock FROM ts_items GROUP BY type ORDER BY type";
String s2 = "SELECT expenditure FROM ts_expenditure GROUP BY type ORDER BY type";
String s3 = "SELECT sales FROM ts_sales GROUP BY type ORDER BY type";
rs1 = stat1.executeQuery(s1);
rs2 = stat2.executeQuery(s2);
rs3 = stat3.executeQuery(s3);
String type;
int cp, sp, stock, expenditure, sales;
while( rs1.next() || rs2.next() || rs3.next() )
{
type = rs1.getString("type");
cp = rs1.getInt("cp");
sp = rs1.getInt("sp");
stock = rs1.getInt("stock");
expenditure = rs2.getInt("expenditure");
sales = rs3.getInt("sales");
info.append("\n" + type + "\t" + cp + "\t" + sp + "\t" + stock + "\t" + expenditure + "\t" + sales);
}
Output:
Runtime Exception: Before start of result set

This is the problem:
while( rs1.next() || rs2.next() || rs3.next() )
If rs1.next() returns true, rs2.next() and rs3.next() won't be called due to short-circuiting. So rs2 and rs3 will both be before the first row. And if rs1.next() returns false, then you couldn't read from that anyway...
I suspect you actually want:
while (rs1.next() && rs2.next() && rs3.next())
After all, you only want to keep going while all three result sets have more information, right?
It's not clear why you're not doing an appropriate join, to be honest. That would make a lot more sense to me... Then you wouldn't be trying to use multiple result sets on a single connection, and you wouldn't be relying on there being the exact same type values in all the different tables.

You do an OR so imagine only one ResultSet has a result.
What you end up with is trying to read from empty result sets.

Suppose rs1 has one result and rs3 has 3 results. Now as per your code it will fail for rs1.getString("type"); during second iteration.
Better to loop over each resultSet separately.

This is going to go badly wrong, in the event that there is a type value that's missing from one of your three tables. Your code just assumes you'll get all of the types from all of the tables. It may be the case for your current data set, but it means that your code is not at all robust.
I would seriously recommend having just one SQL statement, that has each of your three selects as subselects, then joins them all together. Your java can just iterate over the result from this one SQL statement.

I need a sql statement in java that finds an average with a where clause and returns value

So far my code is:
try{
stmt = con.createStatement();
String sql = "SELECT AVG(WPM) FROM Attempts WHERE Username = ('" + Login.loginUsername + "');
rs = stmt.executeQuery(sql);
int add1 = rs.getInt("AVG(WPM)");
System.out.println("avg temp is " + add1);
}
catch (SQLException err) {
System.out.println(err.getMessage());
}
my database is set up like so:
(PK) 'AttemptID' Integer AutoIncrement
'WPM' Integer
(FK) 'Username' Varchar(45)
I want it to return average WPM based on each username. If I change the line
int add1 = rs.getInt("AVG(WPM)");
to
String add1 = rs.getString("AVG(WPM)");
there is no difference. please help.

Try with double add1 = rs.getDouble(1);
Explanaition: rs.get...(1) gets the column based on the column index, not based on the name of the column. The database might change this when using functions in your select. Also, use double instead of int as AVG returns a double.

It looks like that you forget the statement rs.next()...

your sql have SQL injection ..
AVG function result maybe to float or double .
float f = rs.getFloat(1);//

I think you simply need to add a group by clause to your select statement. Your select statement would then read: select avg(WPD) from Attempts group by Usename where Username = ... That should correctly calculate the average WPD per user. Since you are using average I would think that the value returned is likely a double. In that case you should use rs.getDouble. Only a single value is selected in the query so you can use the index of the column to access it. The call will then be rs.getDouble(0). I hope you find this answer helpful.
Good luck,
Nikolai