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Android studio can't connect to database in Azure sql server

I am using android studio to develop an application and using Azure Sql Server to host my database. The problem is I was able to connect to my database on SQL server but it has an error of Object not found in my database.
I found out that it might be connecting to my master database instead of the database I want it to connect to. Is there any solution to solve the problem?
package com.example.lenovo.testing1;
import android.annotation.SuppressLint;
import android.os.StrictMode;
import android.util.Log;
import java.sql.*;
public class ConnectionClass {
String hostName = "haozailai.database.windows.net";
String dbName = "haozailai";
String user = "username";
String password = "password";
#SuppressLint("NewApi")
public Connection CONN() {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
String ConnURL;
Connection conn = null;
try {
Class.forName("net.sourceforge.jtds.jdbc.Driver");
String url = String.format("jdbc:jtds:sqlserver://haozailai.database.windows.net:1433;database=haozailai;user=username;password=password;encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;");
conn = DriverManager.getConnection(url);
}catch (SQLException se)
{
Log.e("error here 1 : ", se.getMessage());
}
catch (ClassNotFoundException e)
{
Log.e("error here 2 : ", e.getMessage());
}
catch (Exception e)
{
Log.e("error here 3 : ", e.getMessage());
}
return conn;
}
}
Picture of my database structure

I tried to connect my sqlserver via java jdbc and did not reproduce your issue.
I can connect to my application db successfully.
My test code:
import java.sql.*;
public class Test {
public static final String url = "jdbc:sqlserver://***.database.windows.net:1433;database=***;user=***password=***;encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;";
public static final String name = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
public static Connection conn = null;
public static PreparedStatement pst = null;
public static Statement stmt = null;
public static ResultSet rs = null;
public static void main(String[] args) {
try {
String SQL = "select * from dbo.Student";
Class.forName(name);
conn = DriverManager.getConnection(url);
stmt = conn.createStatement();
rs = stmt.executeQuery(SQL);
while (rs.next()) {
System.out.println(rs.getString("name"));
}
close();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void close() {
try {
conn.close();
stmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
After some research, I found out it is because of your connect url.
You need to modify your connect url ：
jdbc:jtds:sqlserver://haozailai.database.windows.net:1433/<your application db name> ...
You could refer to the pages below for more details.
https://sourceforge.net/p/jtds/discussion/104389/thread/a672d758/
how to connect sql server using JTDS driver in Android
Update answer:
I have made a slight adjustment to your connect URL and can connect to my application database normally.
try {
String SQL = "select * from dbo.Student";
Class.forName("net.sourceforge.jtds.jdbc.Driver");
String url = String.format("jdbc:jtds:sqlserver://***.database.windows.net:1433/<your database name>;user=***;password=***;encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;");
conn = DriverManager.getConnection(url);
stmt = conn.createStatement();
rs = stmt.executeQuery(SQL);
while (rs.next()) {
System.out.println(rs.getString("name"));
}
close();
} catch (Exception e) {
e.printStackTrace();
}
Notice that remove the database=*** and add "/<your database name>" after your host string.
Please refer to the above code and try again.Any concern, please let me know.
Hope it helps you.

I know this answer is waay too late, but I found this video that totally works: https://www.youtube.com/watch?v=WJBs0zKGqH0
The thing is, you have to download a jtds jar, the guy in the video says where you can get it from and also, you need to add "jtds" before "sqlserver" in connection url and edit the way the 'databe' is written in the connection url, like this:
jdbc:jtds:sqlserver://serverName.database.windows.net:portNr:DatabaseName=dbName;user=....

Transact SQL Statements from java to Ms SQL Server 2014

Good morning developers (Its morning in Kenya). I have been working with Java and MySql databases. my newest client want me to create a solution based on his current installed database, running Microsoft Sql Server 2014 Enterprise Edition.
The code below connects to the SQL Server instance but cannot transact any SQL Statements. i get the SQL Exception "Invalid Object Name". Please troubleshoot the code for me. thank you.
private java.sql.`enter code here`Connection con = null;
private final String url = "jdbc:sqlserver://";
private final String serverName = "localhost\\PHILIP";
private final String portNumber = "1433";
private final String databaseName = "Payrol";
private final String userName = "sa";
private final String password = "kukaphilip";
public Main() {
System.setProperty("java.net.preferIPv6Addresses", "true");
getConnection();
}
private String getConnectionUrl() {
//System.out.println(java.lang.System.getProperty("java.library.path"));
return "jdbc:jtds:sqlserver://localhost;Database=Payrol;integratedSecurity=true";
}
private java.sql.Connection getConnection() {
try {
/*Class.forName("net.sourceforge.jtds.jdbc.Driver");*/
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
con = DriverManager.getConnection(getConnectionUrl());
if (con != null) {
System.out.println("Connection Successful!");
String sql = "INSERT INTO payrol.dbo.test values('1','Philip')";
Statement st = con.createStatement();
st.executeUpdate(sql);
/*st.setInt(1, 1);
st.setString(2, "Philip");
st.execute();*/
}else{
System.out.println("Connection failed");
}
} catch (SQLException e) {
System.out.println(e.getMessage());
} catch (ClassNotFoundException ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}
return con;
}

Check These
1)Try executing same query in SSMS to see if you get any error.
2)Put payrol.dbo.test into square brackets like [payrol].[dbo].[test]
3) If collation is case sensitive the cases of 'test' must be identical in database and in your query.

How to connect JDBC to tns oracle

I can connect from plsql to database using tns file
Now I want to connect to the database from my Java using JDBC.
What I tried:
I search google and I find that I have to using this connection String:
"jdbc:oracle:thin:#//host:port))/tnsfile)";
My computer name is myPC
The port that is written in the tnsfile is 5151
So I tried this connection String
"jdbc:oracle:thin:#//myPC:5151))/tnsfile"
but I got this Exception
java.sql.SQLRecoverableException: IO ERROR: SO Exception was generated
What am I doing wrong?
How to connect my JDBC to the database using tns file?

You have to set a property named oracle.net.tns_admin to point to the location of the folder containing your tnsnames.ora file. Then you specify the entry from that file after the # sign in your DB URL. Check example below. You can find more information here: Data sources and URLs - Oracle Documentation
import java.sql.*;
public class Main {
public static void main(String[] args) throws Exception {
System.setProperty("oracle.net.tns_admin", "C:/app/product/11.2.0/client_1/NETWORK/ADMIN");
String dbURL = "jdbc:oracle:thin:#ENTRY_FROM_TNSNAMES";
Class.forName ("oracle.jdbc.OracleDriver");
Connection conn = null;
Statement stmt = null;
try {
conn = DriverManager.getConnection(dbURL, "your_user_name", "your_password");
System.out.println("Connection established");
stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT dummy FROM dual");
if (rs.next()) {
System.out.println(rs.getString(1));
}
} catch (Exception e) {
e.printStackTrace();
}
finally {
if (stmt != null) try { stmt.close(); } catch (Exception e) {}
if (conn != null) try { conn.close(); } catch (Exception e) {}
}
}
}
Example entry from tnsnames.ora file:
my_net_service_name=
(DESCRIPTION=
(ADDRESS=(some address here))
(CONNECT_DATA=
(SID=some_SID_name)))
Where my_net_service_name string is what you have to subsitite for ENTRY_FROM_TNSNAMES from my Java example.

Rather than hard code the path to tnsnames.ora, better to find it from the environment:
public static void setTnsAdmin() {
String tnsAdmin = System.getenv("TNS_ADMIN");
if (tnsAdmin == null) {
String oracleHome = System.getenv("ORACLE_HOME");
if (oracleHome == null) {
return; //failed to find any useful env variables
}
tnsAdmin = oracleHome + File.separatorChar + "network" + File.separatorChar + "admin";
}
System.setProperty("oracle.net.tns_admin", tnsAdmin);
}

Try the following:
System.setProperty("oracle.net.tns_admin", PATH_TO_TNSNAMES.ORA);
Class.forName ("oracle.jdbc.OracleDriver");
dbUrl = "jdbc:oracle:thin:#(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST="+IPHOST+")(PORT="+PORT+"))(CONNECT_DATA=(SERVER = DEDICATED)(SERVICE_NAME="+DBNAME+")))"
conn = DriverManager.getConnection(dbUrl, USERNAME, PASSWORD);
Be sure to have the latest version of ojdbc.jar

java.sql.SQLException: No database selected - why?

the last days I was trying to learn how to access mySQL databases via Java.
I am able to load the driver and get a connection to the database ( at least I think so, since I don't get an exception there..)
the code is:
import java.sql.*;
public class test
{
public static void main(String[] args)
{
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("driver loaded...");
}
catch(ClassNotFoundException e){
System.out.println("Error in loading the driver..."+e);
System.exit(0);
}
try
{
Connection dbConnection= DriverManager.getConnection("jdbc:odbc:test","root","password");
System.out.println("Connection successful...");
Statement stmt = dbConntection.createStatement();
stmt.executeUpdate("create table Accounts ( name char(20) )");
}
catch(SQLException e)
{
System.out.println("database-ConnectionError: "+e);
System.exit(0);
}
}
}
When I execute it, it says:
driver loaded... Connection successful...
database-ConnectionError: java.sql.SQLException: [MySQL][ODBC 5.2(w) Driver][mysqld-5.5.31]No database selected
I really don't know the problem, because I thought the database is selected during the "getConnection" process....
I tried to select a database by adding this line:
stmt.executeUpdate("use test;");
after creating the Statement.
unfortunately it didn't work because I got another exception which said I should check on the syntax. I don't understand that either because in my commandline it works just fine...
I don't know if it is possible to use these type of commands via Java so if it isn't, please forgive my mistake.
I hope you can help me and I didn't miss the solution during my own search!
Already Thanks to all who reply and use their time on my problems!
ps. If I forgot to point out some important infos ( I don't think i did) please ask:)
edit: I also tried to create a new database during runtime
stmt.executeUpdate("CREATE DATABASE test;");
this actually works, but the database won't be selected either...

Before you can add a table, you first have to select a database.
you can create a new database with:
CREATE DATABASE database_name
you can connect to a specific database with:
String url = "jdbc:mysql://localhost/databasename";
String username = "test";
String password = "test";
Connection connection = DriverManager.getConnection(url, username, password);

Firstly, I am considering my answer to show you another better way for connection with MySQL Database, it's much easier and less nu-expected Exception(s).
You need to do some steps:
Download Connector/J and add it to your class path(if you are using an IDE there is add the .jar to the library, or there is many tuts on YouTube).
Create your database in your MySQL program.
See this example below example below I made for you demonstrates how to connect and execute queries on MySQL :
import java.sql.*;
public class MySqlConnection {
private String MYSQL_DRIVER = "com.mysql.jdbc.Driver";
private String MYSQL_URL = "jdbc:mysql://localhost:3306/test";
private Connection con;
private Statement st;
private ResultSet rs;
public MySqlConnection() {
try {
Class.forName(MYSQL_DRIVER);
System.out.println("Class Loaded....");
con = DriverManager.getConnection(MYSQL_URL,"","");
System.out.println("Connected to the database....");
st = con.createStatement();
int c =st.executeUpdate("CREATE TABLE Accounts (Name VARCHAR(30))");
System.out.println("Table have been created.");
System.out.println(c+" Row(s) have been affected");
con.close();
} catch(ClassNotFoundException ex) {
System.out.println("ClassNotFoundException:\n"+ex.toString());
ex.printStackTrace();
} catch(SQLException ex) {
System.out.println("SQLException:\n"+ex.toString());
ex.printStackTrace();
}
}
public static void main(String...args) {
new MySqlConnection();
}
}

Here is your updated example, which works for me.
public static void main(String[] args) throws InstantiationException,
IllegalAccessException {
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
System.out.println("driver loaded...");
} catch (ClassNotFoundException e) {
System.out.println("Error in loading the driver..." + e);
System.exit(0);
}
try {
Connection dbConnection = DriverManager
.getConnection("jdbc:mysql://localhost/test?user=root&password=password");
System.out.println("Connection successful...");
Statement stmt = dbConnection.createStatement();
stmt.executeUpdate("create table Accounts ( name char(20) )");
} catch (SQLException e) {
System.out.println("database-ConnectionError: " + e);
System.exit(0);
}
}
Make sure you have added a proper mysql-connector to your build path. I used the: mysql-connector-java-5.1.24-bin.jar

static final String DB_URL = "jdbc:mysql://localhost:3306/sys";
Use database name in the URL.
It worked for me

How to connect to Oracle DB using JDBC connection with out opening Oracle in my machine

Hi Below is the code I wrote for connecting to Oracle DB using JDBC connection and return some values. But this code establish the connection and returns the result if I am opening the oracle toad in my machine.
But when the oracle toad is closed and try to run this code, it will not connect.
Please let me knwo how to connect to oracle DB with out opening the oracle toad manually.
package library;
import java.io.IOException;
import java.sql.*;
public class DBAutomationConnection {
public static void main(String args[]) throws ClassNotFoundException, IOException, SQLException {
DBAutomationConnection dbconn = new DBAutomationConnection();
//Connection conn = dbconn.DBConnection1();
dbconn.DBConnection1("select * from employee where empid='test123'","ROLE_NAME");
}
public void DBConnection1(String query, String colName)throws IOException, ClassNotFoundException{
Connection connection = null;
Statement stmt = null;
try {
// Load the JDBC driver
String driverName = "oracle.jdbc.driver.OracleDriver";
Class.forName(driverName);
connection = DriverManager.getConnection("jdbc:oracle:thin:#//testhostname:1528/ServiceName", "XXAAA_U", "Jw9S");
System.out.println("Connection successful: " +connection);
try {
stmt = connection.createStatement();
ResultSet rs = stmt.executeQuery(query);
while (rs.next()) {
//String UserID = rs.getString("USER_ID");
String UserID = rs.getString(colName);
System.out.println(UserID);
}
} catch (SQLException e ) {
System.out.println("Could not execute query.");
//JDBCTutorialUtilities.printSQLException(e);
} finally {
if (stmt != null) { stmt.close(); }
}
} catch (SQLException e) {
System.out.println("Could not connect to the database");
}
}

You should initialize Oracle TNS-Listener Service from your OS settings>services. You may need to check your tns configuration.

you need to install ORACLE client in your system to connect oracle remotely.
http://www.oracle.com/technetwork/database/features/instant-client/index-097480.html

Do you have Oracle Thin driver installed in your system? This link can guide you.