I am trying to connect to MSSQL server 2008 on my localhost, but I am getting Errors
WARNING: ConnectionID:2 Prelogin error: host 127.0.0.1 port 1434 Error reading prelogin response: Connection reset
this error repeats like 20 times very quickly, then i get
com.microsoft.sqlserver.jdbc.SQLServerException: Connection reset
I suspect this is some wrong configuration of server. I can connect to external servers with no issues. I can also connect via management studio with no problems.
Please help me, I am getting sick of this issue :|
1) TCP protocol for MSSQL 2008 is disabled by default. You need to enable it from SQL Configuration Manager (in the same [Start], Programs folder as MSSQL):
http://msdn.microsoft.com/en-us/library/ms190425%28v=sql.105%29.aspx
2) To use TCP connections (even on localhost!) you need to allow MSSQL in Windows Firewall:
http://technet.microsoft.com/en-us/library/cc646023.aspx
3) You don't necessarily need to use TCP/IP in order to access MSSQL:
http://msdn.microsoft.com/en-us/library/ms187892%28v=sql.105%29.aspx
'Hope that helps!
To connect to MSSQL Server from a Java application, you need to use the JDBC API. The JDBC API provides classes and methods that connect to the database, load the appropriate driver, send SQL queries, retrieve results etc.
HOW TO CONNECT TO THE DATABASE A ‘Connection’ object represents a connection with a database. To establish the connection, use the method ‘DriverManager.getConnection’. This method takes a string containing a URL which represents the database we are trying to connect to. Below is the sample code for establishing a connection:
private String DATABASE_URL = "jdbc:odbc:embedded_sql_app"; // establish connection to database
Connection connection = DriverManager.getConnection( DATABASE_URL,"sa","123" );
Detailed discussion about the Database URL and how to create it can be found in the resource provided at the end of this post.
QUERYING THE DATABASE The JDBC API provides three interfaces for sending SQL statements to the database, and corresponding methods in the ‘Connection’ interface create instances of them. 1. Statement - created by the ‘Connection.createStatement’ methods. A ‘Statement’ object is used for sending SQL statements with no parameters.
2. PreparedStatement - created by the ‘Connection.prepareStatement methods’. A ‘PreparedStatement’ object is used for precompiled SQL statements. These can take one or more parameters as input arguments (IN parameters).
3. CallableStatement - created by the ‘Connection.prepareCall’ methods. ‘CallableStatement’ objects are used to execute SQL stored procedures from Java database applications.
RETRIEVING THE RESULT A ‘ResultSet ‘is a Java object that contains the results of executing a SQL query. The data stored in a ‘ResultSet’ object is retrieved through a set of get methods that allows access to the various columns of the current row. The ‘ResultSet.next’ method is used to move to the next row of the ‘ResultSet’, making it the current row. The following code fragment executes a query that returns a collection of rows, with column ‘a’ as an ‘int’, column ‘b’ as a ‘String’, and column ‘c’ as a ‘float’:
java.sql.Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM Table1");
while (rs.next()) { // retrieve and print the values for the current row
int i = rs.getInt("a");
String s = rs.getString("b");
float f = rs.getFloat("c");
System.out.println("ROW = " + i + " " + s + " " + f); }
This is just a brief introduction on how to interact with a database from Java. For more details on the items discussed above as well as information on passing parameters, executing stored procedures etc. please refer to the following resource: ( http://www.shahriarnk.com/Shahriar-N-K-Research-Embedding-SQL-in-C-Sharp-Java.html#Shahriar_N_Embedding_SQL_in_Java ) Here, you will also find information on how to interact with a database programmatically; i.e. without using SQL. Hope you find this useful.
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I'm working on a project and I have put my database folder in project folder. How can I make a database connection to any directory rather than just default MySQL dir in Java?
String MySQLURL = "jdbc:mysql://localhost:3306/C:\\Program Files\\SnakeGame";
String UserName = "root";
String Password = "admin";
Connection con = null;
try {
con = DriverManager.getConnection(MySQLURL,UserName,Password);
if (con != null) {
System.out.println("Database connection is successful !!!!");
}
} catch (Exception e) {
e.printStackTrace();
}
When doing this, I get this error:
java.sql.SQLSyntaxErrorException: Unknown database 'c:\program files\snakegame'
Your connection URL is wrong
String MySQLURL = "jdbc:mysql://localhost:3306/C:\\Program Files\\SnakeGame";
I am not sure why your MySQLURL contains C:\Program Files\SnakeGame
The connection URL for the mysql database is
jdbc:mysql://localhost:3306/[DatabaseName]
Where jdbc is the API, mysql is the database, localhost is the server name on which mysql is running (we may also use the server's IP address here), 3306 is the port number, and [DatabaseName] is the name of the database created on the MySQL server.
Replace the [DatabaseName] name accordingly after creating the database in MySQL server
Combining localhost:3306/ with C:\\Program Files\\SnakeGame makes little sense for any database - either you're trying to connect to a file-based database (in which case the localhost... part makes no sense) or you're working with a server-based one (in which case the C:\... part makes no sense.
Also, this connection string would make little sense for a file-based database either because you didn't specify a specific file, just a path.
Incidentally, MySQL is server-based, not file-based. It's expecting a database name after the localhost:3306/ part, not a path (hence the error). The physical location of the actual database program is an installation/configuration issue - it has nothing to do with how you actually connect to the database server once it's already running.
Think about it this way: when you call an external database, web service, or web site, do you need to know which physical folder it's deployed to? Obviously not. The physical folders involved are completely irrelevant when calling MySQL or another database like this.
One of the comments pointed this out, but did you intend to use SQlite or some other file-based database here instead?
I am trying to connect to a remote oracle database in java stored procedure in a traditional way. I am able to call the java stored procedure successfully. But I receive the exception "Missing In or Out parameter at Index 1" while making the connection. I am not sure how this error is related to making a connection in any way. But I don't have any other piece of code in java.
try{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection con=DriverManager.getConnection(
"jdbc:oracle:thin:#host:port:servicename","user","pwd");
}catch(Exception e){
//(Missing In or Out parameter at index 1)
//logged the error in the local database table
}
Can someone please help me where I need to make a change to connect to another oracle database.
Connection URL for servicename and sid differ.
Format:
With SERVICE NAME: jdbc:oracle:thin:#//host:port/ServiceName
With SID: jdbc:oracle:thin:#host:port:SID
I need to extract data from a remote Sql server database. I am using the mssql jdbc driver.
I noticed that often dwhen retrieving rows from the database the process suddenly hangs, giving no errors. It remains simply stuck and no more rows are processed.
The code to read from the database is the following:
String connectionUrl = "jdbc:sqlserver://10.10.10.28:1433;databaseName=MYDB;user=MYUSER;password=MYPWD;selectMethod=direct;sendStringParametersAsUnicode=false;responseBuffering=adaptive;";
String query = "SELECT * FROM MYTABLE";
try (Connection sourceConnection = DriverManager.getConnection(connectionUrl);
Statement stmt = sourceConnection.createStatement(SQLServerResultSet.TYPE_SS_SERVER_CURSOR_FORWARD_ONLY, SQLServerResultSet.CONCUR_READ_ONLY) ) {
stmt.setFetchSize(100);
resultSet = stmt.executeQuery(query);
while (resultSet.next()) {
// Often, after retrieving some rows, process remains stuck here
}
}
Usually the connection is established correctly, some rows are fetched, than at some point the process can become stuck in retrieving the next rows batch, giving no errors and not processing any new row. This happens some times, other times it completes succesfully.
AFAIK the only reason I can see is that at some point a connection problem occurs with the remote machine, but shouldn't I be notified of this from the driver?
I am not sure how I should handle these type of situations...is there anything I can do on my side to let the process complete even if there is a temporary connection problem with the remote server (of course if the connection is not recoverable there is nothing I can do)?
As another test, instead of the java jdbc driver I've tried the bcp utility to extract data from the remote database and even with this native utility I can observe the same problem: sometimes it completes succesfully, other times it retrieves some rows (say 20000) and then becomes stuck, no errors and no more rows processed.
I am trying to connect to sql server using by Java application. While connecting to H2 database, I appended schema=schema_name to the connection string in my java application and that worked.
However the same does not works for sqlserver.Connection is established but if my query does not contains the schema name prior to table name then query execution fails.
Please let me know of JDBC supports schema name in connection string or their is any other way.
Sadly, that is not possible. What you might want to do is set default schema for that user instead.
create login foo with password = "superstronkpassword";
create user foober for login foo with default_schema = "my super schema";
I have condition where there are some table from one database (in mssql) which will be copied into another database. The copying time must be when a specific time, which will be given from application. In my case, I use Java programming. Is there any easiest way to do that?
Create a SQL Agent Job in MS SQL Server that copies your data from one database to the other. Then in your Java app connect to the MS SQL Server and start the SQL Server Agent Job.
Connection rConn = //Your Connection details
CallableStatement cs = rConn.prepareCall("EXECUTE dbo.sp_start_job N'your job name'");
boolean checkvar = cs.execute();
You will need to connect to the MSDB database and the account you connect with needs to be in the sysadmin role or the SQLAgentOperatorRole
You SQL statement in your job may look something like this:
INSERT INTO DestinationDatabseName.dbo.DestinationTable (ColumnNames)
SELECT YourColumns
FROM SourceDatabaseName.dbo.SourceTable