In this article Barry Mavin, CEO and Chief Software Architect for Recital, details on how to use the Client Drivers provided with the Recital Database Server to work with local or remote server-side JDBC data sources.
Overview
The Recital Universal .NET Data Provider provides connectivity to the Recital Database Server running on any supported platform (Windows, Linux, Unix, OpenVMS) using the RecitalConnection object.
The Recital Universal JDBC Driver provides the same functionality for java applications.
The Recital Universal ODBC Driver provides the same functionality for applications that use ODBC.
Each of the above Client Drivers use a connection string to describe connections parameters.
The basic format of a connection string consists of a series of keyword/value pairs separated by semicolons. The equals sign (=) connects each keyword and its value.
The following table lists the valid names for keyword/values.
| Name | Default | Description |
|---|---|---|
|
Data Source |
The name or network address of the instance of the Recital Database Server which to connect to. | |
| Directory | The target directory on the remote server where data to be accessed resides. This is ignored when a Database is specified. | |
|
Encrypt |
false | When true, DES3 encryption is used for all data sent between the client and server. |
| Initial Catalog -or- Database |
The name of the database on the remote server. | |
| Password -or- Pwd |
The password used to authenticate access to the remote server. | |
| User ID | The user name used to authenticate access to the remote server. | |
|
Connection Pooling |
false | Enable connection pooling to the server. This provides for one connection to be shared. |
| Logging | false | Provides for the ability to log all server requests for debugging purposes |
| Rowid | true | When Rowid is true (the default) a column will be post-fixed to each SELECT query that is a unique row identifier. This is used to provide optimised UPDATE and DELETE operations. If you use the RecitalSqlGrid, RecitalSqlForm, or RecitalSqlGridForm components then this column is not visible but is used to handle updates to the underlying data source. |
| Logfile | The name of the logfile for logging | |
| Gateway |
Opens an SQL gateway(Connection) to a foreign SQL data source on
the remote server.
servertype@nodename:username/password-database e.g. oracle@nodename:username/password-database mysql@nodename:username/password-database postgresql@nodename:username/password-database -or- odbc:odbc_data_source_name_on_server oledb:oledb_connection_string_on_server jdbc:jdbc_driver_path_on_server;jdbc:Recital:args |
To connect to a server-side JDBC data source, you ue the gateway=value key/value pair in the following way.
gateway=jdbc:jdbc_driver_path_on_server;jdbc:Recital:args
You can find examples of connection strings for most ODBC and OLE DB data sources by clicking here.
Example in C# using the Recital Universal .NET Data Provider:
////////////////////////////////////////////////////////////////////////
// include the references below
using System.Data;
using Recital.Data;
////////////////////////////////////////////////////////////////////////
// The following code example creates an instance of a DataAdapter that
// uses a Connection to the Recital Database Server, and a gateway to
// Recital Southwind database. It then populates a DataTable
// in a DataSet with the list of customers via the JDBC driver.
// The SQL statement and Connection arguments passed to the DataAdapter
// constructor are used to create the SelectCommand property of the
// DataAdapter.
public DataSet SelectCustomers()
{
string gateway = "jdbc:/usr/java/lib/RecitalJDBC/Recital/sql/RecitalDriver;"+
"jdbc:Recital:Data Source=localhost;database=southwind";
RecitalConnection swindConn = new
RecitalConnection("Data Source=localhost;gateway=\""+gateway+"\");
RecitalCommand selectCMD = new
RecitalCommand("SELECT CustomerID, CompanyName FROM Customers", swindConn);
selectCMD.CommandTimeout = 30;
RecitalDataAdapter custDA = new RecitalDataAdapter();
custDA.SelectCommand = selectCMD;
swindConn.Open();
DataSet custDS = new DataSet();
custDA.Fill(custDS, "Customers");
swindConn.Close();
return custDS;
}
Example in Java using the Recital Universal JDBC Driver:
//////////////////////////////////////////////////////////////////////// // standard imports required by the JDBC driver import java.sql.*; import java.io.*; import java.net.URL; import java.math.BigDecimal; import Recital.sql.*; ////////////////////////////////////////////////////////////////////////
// The following code example creates a Connection to the Recital // Database Server, and a gateway to the Recital Southwind database. // It then retrieves all the customers via the JDBC driver. public void SelectCustomers() { // setup the Connection URL for JDBC String gateway = "jdbc:/usr/java/lib/RecitalJDBC/Recital/sql/RecitalDriver;"+ "jdbc:Recital:Data Source=localhost;database=southwind"; String url = "jdbc:Recital:Data Source=localhost;gateway=\""+gateway+"\";
// load the Recital Universal JDBC Driver new RecitalDriver(); // create the connection Connection con = DriverManager.getConnection(url); // create the statement Statement stmt = con.createStatement(); // perform the SQL query ResultSet rs = stmt.executeQuery("SELECT CustomerID, CompanyName FROM Customers"); // fetch the data while (rs.next()) { String CompanyID = rs.getString("CustomerID"); String CompanyName = rs.getString("CompanyName"); // do something with the data... } // Release the statement stmt.close(); // Disconnect from the server con.close(); }
Unfortunately java does not support __FILE__ and __LINE__ but you can get the same functionality with this code which can be placed in one of your libraries.
public static void showTrace(String msg)
{
if (msg.length() > 0) System.out.println(msg);
System.out.println("Trace: " +
"file " + new Throwable().getStackTrace()[1].getFileName() +
" class " + new Throwable().getStackTrace()[1].getClassName() +
" method " + new Throwable().getStackTrace()[1].getMethodName() +
" line " + new Throwable().getStackTrace()[1].getLineNumber());
}
http://kbala.com/ie-9-supports-corner-radius/
auth sufficient pam_krb5.so try_first_pass
auth sufficient pam_unix.so shadow nullok try_first_pass
account required pam_unix.so broken_shadow
account [default=bad success=ok user_unknown=ignore] pam_krb5.so
APPEND FROM TYPE CSV <file-name.csv>The TYPE keyword has now been enhanced to support a comma separated values (CSV) format
If you have a live linux site that is running vmware virtual machines, you can pause the virtual machines when you want to perform a backup, I use acronis for linux which does incremental backups and you can specify a command to run before and after the backup, this allows backups to be performed at scheduled times daily without any intervention. In my examples below, the virtual machine i want to control is in /root/vmware/Recital/Recital.vmx
To pause the virtual machine on linux:
# vmrun pause /root/vmware/Recital/Recital.vmx
and then to unpause after the backup has completed:
# vmrun unpause /root/vmware/Recital/Recital.vmx
That is basicallty it, no need to attend the backup and it can be perfomed at a suitable time so no users are affected.
Incidentally, vmrun lets you startup a virtual machine at system startup too, without needing the GUI:
# vmrun start /root/vmware/Recital/Recital.vmx
Or alternatively stop it:
# vmrun stop /root/vmware/Recital/Recital.vmx
There are lots of other capabilities of this command, running applications inside the virtual machine etc etc. For full details just type vmrun in a terminal window.
./configure CFLAGS='-arch x86_64' APXSLDFLAGS='-arch x86_64' --with-apxs=/usr/sbin/apxsThen you must pass the these additional flags to the apxs command in order to generate a Universal Binary shared module.
-Wl,-dynamic -Wl,'-arch ppc' -Wl,'-arch ppc64' -Wl,'-arch i386' -Wl,'-arch x86_64' -Wc,-dynamic -Wc,'-arch ppc' -Wc,'-arch ppc64' -Wc,'-arch i386' -Wc,'-arch x86_64'If you then do a file command on the shared module it should return;
$ file mod_recital.so mod_recital2.2.so: Mach-O universal binary with 4 architectures mod_recital2.2.so (for architecture ppc7400): Mach-O bundle ppc mod_recital2.2.so (for architecture ppc64): Mach-O 64-bit bundle ppc64 mod_recital2.2.so (for architecture i386): Mach-O bundle i386 mod_recital2.2.so (for architecture x86_64): Mach-O 64-bit bundle x86_64The apache module files are stored in the /usr/libexec/apache2/ directory on a default apache install on the Mac and the configuration file is /private/etc/apache2/httpd.conf
$hdiutil create /tmp/tmp.dmg -ov -volname "RecitalInstall" -fs HFS+ -srcfolder "/tmp/macosxdist/"
$hdiutil convert /tmp/tmp.dmg -format UDZO -o RecitalInstall.dmg