I've tried most of the examples found here and the web, but I can't open a MS access database(2002 or 2013) and get an updatable result set using UCanAccess. The same code using the JDBC:ODBC driver/connection/works. I've written short test code to check concur_updatable to check this, so I must be missing something. I'm using JDK 1.7 on a Win7 machine. I also have another machine with the same results.
This works:
/*
class jdbc, for testing jdbc:odbc CONCUR_UPDATABLE.
*/
import java.sql.*;
public class jdbc {
private static String dbFQN;
public static void main(String[] args) {
try {
dbFQN = ("C:\\phil\\programming\\kpjl2002.mdb");
String database = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=" + dbFQN;
System.out.println("Loading database: " + database);
Connection conn = DriverManager.getConnection(database, "", "");
Statement s = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
// Fetch records from table
String selTable = "SELECT * FROM " + "tblLibrary" + " ORDER BY Artist, Cat, Cart";
s.execute(selTable);
ResultSet rs = s.getResultSet();
int concurrency = rs.getConcurrency();
if(concurrency == ResultSet.CONCUR_UPDATABLE)
{
System.out.println("rs is updatable");
} else {
System.out.println("rs Not updatable");
}
s.close();
conn.close();
} //close try
catch (Exception ex) {
ex.printStackTrace();
} //close catch
} //close main method
} //close dbAccess class
The output is that rs is updatable.
This doesn't work:
/*
class ucan, for testing ucanaccess CONCUR_UPDATABLE.
C:\jdk1.7.0_79\jre\lib\ext\ucanaccess-2.0.9.5.jar
C:\jdk1.7.0_79\jre\lib\ext\hsqldb.jar
C:\jdk1.7.0_79\jre\lib\ext\jackcess-2.1.0.jar
C:\jdk1.7.0_79\jre\lib\ext\commons-lang-2.6.jar
C:\jdk1.7.0_79\jre\lib\ext\commons-logging-1.1.1.jar
also present:
C:\jdk1.7.0_79\jre\lib\ext\commons-logging-1.2.jar
C:\jdk1.7.0_79\jre\lib\ext\commons-lang3-3.4.jar
*/
import java.sql.*;
public class ucan {
private static String dbFQN;
public static void main(String[] args) {
try {
dbFQN = ("C:\\phil\\programming\\kpjl2002.mdb");
String database = "jdbc:ucanaccess://" + dbFQN;
System.out.println("Loading database: " + database);
Connection conn = DriverManager.getConnection(database, "", "");
Statement s = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
// Fetch records from table
String selTable = "SELECT * FROM " + "tblLibrary" + " ORDER BY Artist, Cat, Cart";
s.execute(selTable);
ResultSet rs = s.getResultSet();
int concurrency = rs.getConcurrency();
if(concurrency == ResultSet.CONCUR_UPDATABLE)
{
System.out.println("rs is updatable");
} else {
System.out.println("rs Not updatable");
}
s.close();
conn.close();
} //close try
catch (Exception ex) {
ex.printStackTrace();
} //close catch
} //close main method
} //close dbAccess class
the output is that rs is Not updatable. So I cannot update or insert rows in the resultset.
The code posted is the operative part of a larger project, where UCanAccess can read the table and put the contents in a jList and jTextarea, with formatting. When I started writing code to update or add a new record, I ran into the problem.
I apologize if this is a bit long.
Anybody have an idea what I'm missing or doing wrong?
BTW, this is one of my 2 fav sites for good, usable Java answers.
UPDATE:
Got an idea from old co-worker, the original database may have been copied from an original Access97 db. to a 2000 db. I had used 2013 Repair and Compact to make "new" 2002 and 2013 db's. Access must retain '97 type even when doing what I did. So, I created a new 2013 dummy db to test, and UCanAccess will report resultset as updatable. I will try to recreate the record data of the current db in a new database file, and see if that works. I'm hoping this is the problem, since UCanAccess doesn't support updatability with Access97 db's. I'll let ya'll know what I find.
Thanks.
I had used 2013 Repair and Compact to make "new" 2002 and 2013 db's. Access must retain '97 type even when doing what I did. So, I created a new 2013 dummy db to test, and UCanAccess will report resultset as updatable.
The "Compact and Repair Database" feature in Access does not change the database file version. If you have (what you suspect to be) an older-version database file then you should use the "Save Database As" feature under "File > Save & Publish" * to convert the database file to a newer version.
* (... at least that's where it is in Access 2010.)
Well, after a nice weekend of eating brats and drinking good beer at Germanfest, I finally got things working. I decided to scrap the MS Access db and put the 472 records in a SQLite db. With that, I was able to get PreparedStatements to work to display the records in a jList and JTextArea, add a new record and update a couple fields in an existing record within the same run of the test application. Did it both as a command line run GUI and from NetBeans 8.0, so I think my problems are solved. After a couple of summer projects get done, I'll get back to re-writing the original VB app using Java.
Thanks Gord, and everyone here.
Related
Cheers everyone, beginner here!.
I'm currently working on a Java application to keep track of the inventory in our warehouse. It's all on localhost until it's finished. I've created two tables in MySQL database: one table shows the article code, location and quantity (VOORRAADSYSTEEM); the other table shows article code and description (STAMDATA).
In my GUI, I've got a JTable which loads data from VOORRAADSYSTEEM, and on mouseclickevent (getSelectedRow) shows the data in the corresponding JTextFields (so far so good). The only field not showing is the description field (which should be read from the STAMDATA table).
I've tried creating a method for this specific part of the program. The method runs a query to the second table using a inner join to the first table. Here's the code below.
private void LoadDescription() {
try {
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ABEL?zeroDateTimeBehavior=convertToNull", "root", "");
String sql = "SELECT DESCRIPTION FROM VOORRAADSYSTEEM JOIN STAMDATA ON ARTICLECODE = ARTICLENUMBER WHERE ARTICLECODE="+jComboBox1.getSelectedItem();
pst = conn.prepareStatement(sql);
rs = pst.executeQuery();
pst.setString(2, sql);
descriptionTxt.setText(rs.getString(sql));
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
}
At this moment I'm not exactly sure how to approach this problem. I'm also going to try using foreign keys. Any help would be appreciated.
There are better ways to handle what you want to do. For instance you could get all the information you need with one query by joining the table on a common column (ARTICLENUMBER and ARTICLECODE) and then display it.
Right now it looks/sounds like you might be trying to get all the information with two queries.
However, there are some errors with your load description method:
private void LoadDescription() {
try {
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ABEL?zeroDateTimeBehavior=convertToNull", "root", "");
String sql = "SELECT DESCRIPTION FROM VOORRAADSYSTEEM JOIN STAMDATA ON ARTICLECODE = ARTICLENUMBER WHERE ARTICLECODE="+jComboBox1.getSelectedItem();
ResultSet results = conn.createStatment().executeQuery(sql);
if(results.next()) //make sure something was returned to avoid null pointer exception
descriptionTxt.setText(rs.getString("DESCRIPTION"));
else
JOptionPane.showMessageDialog(null, "no results returned");
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
}
This should work a little better for you.
I am trying to add records to a table in an HSQL database through Java.
I have an HSQL database I made through OpenOffice, renamed the .odb file to .zip and extracted the SCRIPT and PROPERTIES files (It has no data in it at the moment) to a folder "\database" in my java project folder.
The table looks like this in the SCRIPT file
CREATE CACHED TABLE PUBLIC."Season"("SeasonID" INTEGER GENERATED BY DEFAULT AS IDENTITY(START WITH 0) NOT NULL PRIMARY KEY,"Year" VARCHAR(50))
All fine so far, the database connects just fine in Java with this code:
public void connect(){
try{
String dbName = "database\\db";
con = DriverManager.getConnection("jdbc:hsqldb:file:" + dbName, // filenames prefix
"sa", // user
""); // pass
}catch (Exception e){
e.printStackTrace();
}
}
I have the following code to insert a record into "Season".
public void addSeason(String year){
int result = 0;
try {
stmt = con.createStatement();
result = stmt.executeUpdate("INSERT INTO \"Season\"(\"Year\") VALUES ('" + year + "')");
con.commit();
stmt.close();
}catch (Exception e) {
e.printStackTrace();
}
System.out.println(result + " rows affected");
}
I have a final function called printTables():
private void printTables(){
try {
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM \"Season\"");
System.out.println("SeasonID\tYear");
while(rs.next()){
System.out.println(rs.getInt("SeasonID") + "\t\t" + rs.getString("Year"));
}
}catch (Exception e) {
e.printStackTrace(System.out);
}
}
Now if I run this sequence of functions:
connect();
printTables();
addSeason("2010");
printTables();
I get this output:
SeasonID Year
1 rows affected
SeasonID Year
0 2010
Now when I close the program and start it again I get exactly the same output. So the change made during the first run hasn't been saved to the database. Is there something I'm missing?
It's caused by write delay params in hsqldb, by default has 500ms delay synch from memory to files.
So problem is solved when it's set to false
statement.execute("SET FILES WRITE DELAY FALSE");
or set as you like based on your app behaviour.
So my workaround is to close the connection after every update, then open a new connection any time I want to do something else.
This is pretty unsatisfactory and i'm sure it will cause problems later on if I want to perform queries mid-update. Also it's a time waster.
If I could find a way to ensure that con.close() was called whenever the program was killed that would be fine...
I am trying to connect java derby db and insert into a table. Everything goes ok but data is not inserted although there is no error at all. Cn you please let me know whats wrong? i tried to change the code and even created new database n table still same. Code works wihtout error but data is not inserted.
Here is my code
databasetest.java
package databasetest;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
public class DatabaseTest {
public static void main(String[] args) {
try{
Class.forName("org.apache.derby.jdbc.ClientDriver");
System.out.println(" class found " );
}catch(Exception e){
System.out.println("Not found driver class" + e);
};
try{
Connection conn = null;
String pass =null;
conn = DriverManager.getConnection("jdbc:derby://localhost:1527/user","APP",pass);
System.out.println(" Connected to database " );
try{
Statement st;
System.out.println(" inserted");
conn.close();
}catch(Exception e){
System.out.println(" Eror in inserting" + e );
}
}catch(Exception e){
System.out.println("Mistake happnd " + e);
}
}
}
here is run result
run:
class found
Connected to database
inserted
BUILD SUCCESSFUL (total time: 0 seconds)
Please can some one tell me whats going wrong?
Thanks in advance
The problem seems to reside here: Statement st;. You are creating a statement object but you are not associating any queries to it.
Please take a look at this Oracle Tutorial for more information on the matter.
Your code is not actually trying to insert anything.
Statement st;
System.out.println(" inserted");
conn.close();
This doesn't really do anything other than close the connection.
Usually you will want to create a PreparedStatement with a query like
PreparedStatement st = conn.prepareStatement("place your SQL Query here");
st.execute();
alternatively you could look into the API for PreparedStatement.
If you are set on using a regular Statement or your query is simple and does not involve insecure input, you can use
Statement stmt = conn.createStatement();
stmt.execute("Simple SQL Query here");
from the code looks like You have just created the connection with database.
there is no code to insert something into the database.
add the following code to insert some value into your database.
Statement stmt=con.createStatement();
String query="Insert into table_name values (comma separated sequential column value)"; //here comes your insertion query
ResultSet rs=stmt.executeQuery(query);
I have a web application which is based on SQL Server 2012, and I use Java to update data in the database. (Windows Server 2008, JSP, Tomcat7, Java7)
The relevant code is as follows:
public static synchronized int execute(String dsName, String packageAndFunction, List fields) {
// prepare insertStr
String executeStr = buildStatement(dsName, packageAndFunction, null, fields);
dbConn = DBConnection.getInstance();
Connection conn = dbConn.getConnection();
CallableStatement stmt = null;
int result = RESULT_FAILED;
try {
stmt = conn.prepareCall(executeStr);
// fill statement parameters (each ?)
fillStatement(stmt, fields);
stmt.execute();
result = stmt.getInt(fields.size());
} catch(SQLException e) {
Log.getInstance().write("Exception on executeGeneral (" + packageAndFunction + ") " + e.toString());
} finally {
try {
stmt.close();
dbConn.returnConnection(conn);
} catch(SQLException e) {
Log.getInstance().write("Exception on executeGeneral (" + packageAndFunction + ") " + e.toString());
}
}
return result;
}
About 90% of the time, the code works great. The rest of the time there is some kind of lock on the table which will disappear by itself in perhaps half an hour or so. The lock prevents even simple SELECT queries on the table from executing (in SQL Server Management Studio). In severe cases it has prevented the entire application from working.
I had an idea to use stmt.executeUpdate() instead of stmt.execute(), but I have tried to research this and I do not see any evidence that using stmt.execute() for updating causes locks.
Can anyone help?
Thanks!
It's difficult to diagnose with that code. The next time that it happens, pull up your activity monitor on the SQL server and see what sql command is holding the lock.
for a school database project we are making a database program (user GUI and the database). Using Microsoft Access 2010 I created the database and populated it with some sample data, and saved it in .mdb format and placed it in my project folder.
When running it in eclipse the following code works fine, connects and even retrieves the query. However I find that I am unable to export the code to a jar and run it (which is required for the project, give them a working copy of your program on a CD or flash drive), and I'm also unable to port the code over to Netbeans to have it work, as well as trying to compile on a Linux machine.
I assume this is a problem with including drivers or trying to use Microsoft access. The error I get when running the jar or running on Netbeans is given below the code. So I ask either how do I include drivers to make the program portable, or how else can I approach this problem?
Thanks in advance
import java.sql.*;
public class JDBCTest {
static Connection connection;
static Statement statement;
public static void main(String args[]){
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();
String database = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=TLDATABASEDBM.mdb";
connection = DriverManager.getConnection( database ,"","");
buildStatement();
executeQuery();
}catch(Exception e){
e.printStackTrace();
System.out.println("Error!");
}
}
public static void buildStatement() throws SQLException {
statement = connection.createStatement();
}
public static void executeQuery() throws SQLException {
boolean foundResults = statement.execute("SELECT * FROM tblStaff AS x WHERE City='Calgary'");
if(foundResults){
ResultSet set = statement.getResultSet();
if(set!=null) displayResults(set);
}else {
connection.close();
}
}
public static void displayResults(ResultSet rs) throws SQLException {
ResultSetMetaData metaData = rs.getMetaData();
int columns=metaData.getColumnCount();
String text="";
while(rs.next()){
for(int i=1;i<=columns;++i) {
text+=""+metaData.getColumnName(i)+":\t";
text+=rs.getString(i);
//text+="</"+metaData.getColumnName(i)+">";
text+="\n";
}
text+="\n";
}
System.out.println(text);
}
}
The error mentioned above:
java.sql.SQLException: [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified
at sun.jdbc.odbc.JdbcOdbc.createSQLException(JdbcOdbc.java:6957)
at sun.jdbc.odbc.JdbcOdbc.standardError(JdbcOdbc.java:7114)
at sun.jdbc.odbc.JdbcOdbc.SQLDriverConnect(JdbcOdbc.java:3073)
at sun.jdbc.odbc.JdbcOdbcConnection.initialize(JdbcOdbcConnection.java:323)
at sun.jdbc.odbc.JdbcOdbcDriver.connect(JdbcOdbcDriver.java:174)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:207)
at tldatabase.DataConnect.makeConnection(DataConnect.java:35)
at tldatabase.Main.main(Main.java:24)
I know the post was years ago but I felt like answering the question for those who are just experiencing this right now. It took me a while to know the answer to the question so here's the solution:
http://wiki.netbeans.org/FaqSettingHeapSize
Follow the "Running the 32-bit JVM".
All you have to do is find the netbeans.conf in the installation folder of your netbeans and change the directory from something like this:
netbeans_jdkhome="C:\Program Files\Java\jdk1.6.0_24"
to this:
netbeans_jdkhome="C:\Program Files (x86)\Java\jdk1.6.0_21"
The problem is netbeans might be running in 64 bit but MS Access only support 32-bit. So doing this would hopefully solve the problem. Also make sure to install this:
http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=23734
The main problem lies in the line:
String database = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=TLDATABASEDBM.mdb";
Make sure that the .mdb file is in the correct directory.
Check the file extension as .mdb or .mdbacc.
Also, if you want to use the same DSN every time, it is better to add the DSN(Data Source Name) into the respective system on which the mdb is stored.
I think that your app do not see TLDATABASEDBM.mdb in current directory. You can give full path to this file in connection string or add system DSN in ODBC Manager and then connect to it with connection string like: jdbc:odbc:TLDATABASEDBM
Honestly, I dont like what I am going to say... but, it solved the same issue for me... mysteriously... :(((
on the line where you are defining the database variable, I changed ...(.mdb)... into ...(.mdb, *.accdb)...
All the best for figuring out what difference that made!
package javaapplication1;
import java.sql.*;
public class MSaccess_archive {
public static void main(String[] args) {
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
// set this to a MS Access DB you have on your machine
String filename = "mdbTEST.mdb";
String database = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=";
database+= filename.trim() + ";DriverID=22;}"; // add on to the end
// now we can get the connection from the DriverManager
Connection con = DriverManager.getConnection( database ,"","");
Statement stmt = con.createStatement();
stmt.execute("select * from student"); // execute query in table student
ResultSet rs = stmt.getResultSet(); // get any Result that came from our query
if (rs != null)
while ( rs.next() ){
System.out.println("Name: " + rs.getInt("Age") + " ID: "+rs.getString("Course"));
}
stmt.close();
con.close();
}
catch (Exception err) {
System.out.println("ERROR: " + err);
}
}
}