Statement « Connection « Java Database Q&A





1. Is statement.close() explicitly required in connection pooled environment?    stackoverflow.com

I am using connection pooling in my application. My question is: Is it explicitly required to close statement before closing connection in case of connection pooled environment? In connection pooled environment connection is ...

2. JDBC Connection and Statement Classes    stackoverflow.com

Since Connection and Statements are interfaces, interface methods will be abstract by default. How can we create Connection and Statement interfaces in our Java program while connecting to the database? ...

3. Is there any way to prepare a sql statement in Java without using a Connection object?    stackoverflow.com

I'm pretty new to JDBC, so this is probably a very straightforward question. I have to run several SQL statements, so I'm trying to write a generic "runSQLResultSet" method that takes a ...

4. Impact of java.sql.Connection.close() on java.sql.Statement objects and the like    stackoverflow.com

Does closing a java.sql.Connection also close all the statements, prepared statements, etc. obtained from that connection? Or is there going to be memory leak if I close the connection but leave ...

5. Java: Prepare a statement without a connection    stackoverflow.com

I'm trying to generate some sql files in my java application. The application will not execute any sql statements, just generate a file with sql statements and save it. I'd like to use ...

6. Must JDBC Resultsets and Statements be closed separately although the Connection is closed afterwards?    stackoverflow.com

It is said to be a good habit to close all JDBC resources after usage. But if I have the following code, is it necessary to close the Resultset and the ...

7. When to call getWarnings() on Connections, Statements, and ResultSets with JDBC?    stackoverflow.com

In JDBC the Connection, Statement, and ResultSet types each have a getWarnings() method that is specified to produce the first warning associated with objects of that type. The second and subsequent ...

8. Is there a method of doing close from the outside of the method of generating Statement and ResultSet generated from Connection?    stackoverflow.com

I am Japanese. English is unskilled. I'm sorry. Is there a method of doing close from the outside of the method of generating Statement and ResultSet generated from Connection? However, ...

9. JDBC Closing Resources    stackoverflow.com

I am unsure whether a statement and resultset should be closed after each query or after all my queries have been made (ie at the same time i close the connection)? Correct ...





10. Connect and Statement objects...    coderanch.com

Hi, I'm new to JDBC, I just have two quick questions: First, What is the difference between using the Class.forName()method, and the System.setProperty()method to register a driver. When would you use one rather than the other, as they seem to do the same thing? second, What are the advantages / disadvantages of creating one Statement object in the initialization of a ...

11. Using result sets, statements & connections    coderanch.com

I see - I checked out the class in the java.sun docs. I can't see any way though to cater for multiple fields - do vectors or arrays allow more than one dimension, or do I have to use a vector to store each record's fields, and then put that in a vector?

12. Can we execute two sql statements with one Connection object?    coderanch.com

Hi, I have a query application, where users enter query parameters and view results in a multi-page format.I'm trying to reduce the number of database trips made during displaying of results. The way my application currently works is that initially, a query gets a count(*) of rows that matched what the users are trying to look for. If count(*) is greater ...

13. Is it possible to connect 2 select statements into one    coderanch.com

You would want to use a sub query. I am not sure if what I am showing you will work, but it will be something similar to: SELECT [outlet #], [name], address, [city/town], [postal code], telephone, (SELECT COUNT([outlet #])) FROM OM WHERE address LIKE '%' + @address + '%' Hope that helps. BTW - The query will be analized starting with ...

14. Statement.close() & connection.close()    coderanch.com

15. Why close the connection, statement and resultset?    coderanch.com

From what I understand, closing the Connetion Object also closes the Threaded Process on the DBMS. The DBMS will error check these threads most of the time and handle strays, but it is always better to close them when you are finished with them. It will help performance on the DBMS side.

16. Reusing Connection and Statement    coderanch.com





17. closing connection and statement    coderanch.com

18. statement N connection    coderanch.com

20. Help with connection statement    coderanch.com

Hi, I want the initialization of the database i.e., Class.forName(DEFAULT_DRIVER); Connection connection = DriverManager.getConnection(DEFAULT_URL); To be done in one method (in a class) and other methods should use this connection object inside.Is it possible to do something like this.Hope that you got my question correctly. A reply would be appreciated. Thanks AS Also adding, What will be the return type of ...

22. Proper way to close Connection, Statement & ResultSet    coderanch.com

Hello all, I am working in an Application which uses DB2 as the Back end. I am using DAO (Data Access Objects) to do Database operations. In most cases i use Callable Staments to call my stored Procedures to do the work. Assuming that Conn is my 'Connection' object, stmt is my 'Callable Statement' Object & resultSet is my 'ResultSet' object, ...

23. Is there a limit to # of Statements over a Connection object    coderanch.com

Is there a limit or performance pitfall I need to be aware of in terms of how many Statement(PreparedStatements) objects I should create over one Connection object? Currently I have a singleton class where my DB calls are made from. When instantiating the class through static method, I pass in a Connection object that creates about ten preparedstatement objects. Is there ...

24. Connection, Resultset and statement    coderanch.com

One refinement I'd make to that linked page is about closing the objects. You need to catch SQLException to make sure everything gets closed. This is the common pattern.Connection conn = ... Statement stmt = null; ResultSet rs = null; try { stmt = ... rs = ... ... } catch ... finally { if ( rs != null ) { ...

25. Passing a Statement instead of a Connection?    coderanch.com

Could you provide more details , like what kind of sequencial operation you are doing in your code, are all those operation are insert or mixed operation of insert/update. whether they are on same table or multiple tables ? in my view spanning one conection /statement to multiple places makes maintainance difficult in long run. It also make debugging process long. ...

26. Closing a callable statement and connection    coderanch.com

Callable Statement: I have overridden close() method and in that I am closing a statement object. Can I also use it for closing the CallableSatement Object? or Shall I have to write another close() [over ridden] metod to use the callable statement? Connection: I am passing the Connection object as an argument to a methd and after using connection object in ...

27. Connection and Statement    coderanch.com

Hi, I have a question. I have to insert 5 records in a database. I get the connection from datasource and create the preparedStatement. My question is, is it good to use one Connection and preparedStatement to insert all the 5 records or do I have to get the connection using ds.getConnection() and preparedStatement for each insert? Which one would be ...

29. what is correct way to close statement , connection , resultset...    coderanch.com

Raminaa, It is correct to close database resources in a finally block to guarantee they get closed. It is the same idea for statements, connections and resultsets. As an example: try { // database code rs.doStuff... } catch (SQLException e) { // handle exception } finally { if ( rs != null ) { try { rs.close(); catch (SQLException e1) { ...

30. A connection taken from Statement != used for creation it at pooling    coderanch.com

I use Apache connection pool. Generally I close a connection after usage. Sometimes I can't reach an original connection, so I get it from a statement and close. I noticed that an original connection and one gotten from statement are not equal. Why it's so? Is any risk of connections leak when when I close connection from statement ?

31. JDBC Connection successful but havin problems with the SQL Statements in java now :(    coderanch.com

Yes sir.. it's working Thank you. So basically, the strings in an SQL statement should only contain what the database understands like the statement syntax, table, column names etc.. right?/ Everything else should be added with a + symbol.Sry am a beginner so this is what I have understood. Please correct me if I am wrong. I am also trying to ...

33. JDBC Connection Leakage: Closing Connection BEFORE Closing Statement?    coderanch.com

Bob, It's hard to say as it depends on the JDBC driver. If the driver followed the specification, closing the connection would close the statement and the second line would either do nothing silently or throw an exception. If the driver didn't follow the specification, anything could happen. try { conn.close(); } catch (Exception e) {} try { cstmt.close(); } catch ...

34. Alternate way for closing connection ,statements once we get the resultset    coderanch.com

santhosh.R gowda wrote:Dear all, As we know once the connection has been established and statement get created and execute the query untill the result set get closed we cant close the statement and connection is there any other way to close the connection and statement after the statement.executeQuery() method has been called Santhosh, I think your query is NOT legible. Even ...

37. coding database connection statements best practices    forums.oracle.com

public void queryDB () { //code for loading the ODBC driver (MS Access) //code for establishing the DB connection String queryString = "Select * from Employee"; //Statement to execute the (queryString) statement con.close(); } public void addDB { //code for loading the ODBC driver (MS Access) //code for establishing the DB connection String addString = "INSERT INTO Employee VALUES('Bob','Smith',35,56000,121342)"; //Statement to ...

38. About Connection, ResultSet, Statement interfaces....    forums.oracle.com

hi , Connection, ResultSet, Statement etc.. all are the interfaces. But when i am writing the codes like, Statement stmt= con.createStatement(); ResultSet rs= stmt.excuteQuery("select * from student_mst"); where con is the instance of Connection interface. Therefore my question is that since all those(Connection,ResultSet,Statement) are interfaces then how the methods createStatement(),excuteQuery(String sql) are being executed where as those methods are only the ...

39. Closing Connection, Statement and ResultSet    forums.oracle.com