

I am a fan of the previous incarnation of the PlugComputer so I was excited to see that Marvell have unveiled a new PlugComputer dubbed imaginatively "PlugComputer 3.0."
PlugComputer 3.0 Features:
Smaller sleeker design,
More powerful CPU - 2gz Armanda 300 CPU,
120GB 1.8-inch SATA hard drive,
Wifi,
Bluetooth,
10/100/1000 wired Ethernet,
USB 2.0.
512MB of RAM
512MB of Flash memory
I for one would like to see an additional Ethernet port added to increase application flexibility, for some applications where you are using clustered plugs or even for routing, having multiple Ethernet ports is a must.
Even without multiple ethernet ports, these low power consumption devices really could have a place in SME environments, replacing large cumbersome legacy hardware with compact Linux plug servers.
More information about the PlugComputer can be found here
USE accounts INDEX on account_no TAG outstanding FOR balance > 0 EXPLAIN SELECT * FROM accounts WHERE balance > 0 Optimized using for condition on tag 'OUTSTANDING'
In this article Barry Mavin, CEO and Chief Software Architect for Recital, gives details on Working with user-defined Functions in the Recital Database Server.
Overview
User-defined functions (UDFs) are collections of statements written in the Recital 4GL (compatible with Visual FoxPro) stored under a name and saved in a Database. User-defined functions are just-in-time compiled by the Recital database engine. User-defined functions can be used in SQL statements to extend the power and flexibility of the inbuilt functions. Using the Database Administrator in Recital Enterprise Studio, you can easily create, view, modify, and test Stored Procedures, Triggers, and user-defined functions.
Tip
You can also extend the Recital Database Server with C Extension Libraries and use the functions defined within that library also.Creating and Editing user-defined functions
To create a new User-defined function, right-click the Procedures node in the Databases tree of the Project Explorer and choose Create. To modify an existing User-defined function select the User-defined function in the Databases Tree in the Project Explorer by double-clicking on it or selecting Modify from the context menu. By convertion we recommend that you name your User-defined functions beginning with "f_xxx_", where xxx is the name of the table that they are associated with.
Testing the user-defined function
To test run the user-defined function, select it in the Databases Tree in the Project Explorer by double-clicking on it. Once the Database Administrator is displayed, click the Run button to run it.
Example
Example: user-defined function "f_order_details_total".
//////////////////////////////////////////////////////////////////////// // example user-defined function function f_order_details_total(pUnitprice, pQuantity, pDiscount) return (pUnitprice + pQuantity + pDiscount) > 0 endfunc
Example: using the user-defined function in a SQL SELECT statement.
//////////////////////////////////////////////////////////////////////// // sample code to use a user-defined function in a SQL SELECT statement select * from customers where f_order_details_total(Unitprice, Quantity, Discount)
Using user-defined function libraries with the Recital Database Server
You can place all of the user-defined functions associated with a particular table into a procedure library. You then define an Open Trigger for the table that opens up the procedure library whenever the table is accessed. This is a much faster way of using user-defined functions as it reduces the amount of file open/close operations during a query and also simplifies development and maintenance.
By convertion we recommend that you should name the library using the convention "lib_xxx", where xxx is the name of the table that the library is associated with.
Example: procedure library in lib_order_details.
//////////////////////////////////////////////////////////////////////// // example user-defined functions function f_order_details_total(pUnitprice, pQuantity, pDiscount) return (pUnitprice * pQuantity - pDiscount) > 0 endfunc function f_order_details_diff(pUnitprice, pQuantity, pDiscount, pValue) return f_order_details_total(pUnitprice, pQuantity, pDiscount) - pValue endfunc
Example: Open Trigger in dt_order_details_open.
//////////////////////////////////////////////////////////////////////// // This trigger will open up the procedure library when the table is opened set procedure to lib_order_details additive
Example: Close Trigger in dt_order_details_close.
//////////////////////////////////////////////////////////////////////// // This trigger will close the procedure library when the table is closed close procedure lib_order_details
Example: using the user-defined function in a SQL SELECT statement.
//////////////////////////////////////////////////////////////////////// // sample code to use a user-defined function in a SQL SELECT statement select * from customers where f_order_details_total(Unitprice, Quantity, Discount)
User-defined functions can also be used with any of the Client Drivers that work with the Recital Database Server.
iptables -I INPUT -j ACCEPT -p tcp --destination-port 8001 -i lo
iptables -A INPUT -j DROP -p tcp --destination-port 8001 -i eth0
The Recital Oracle Gateway requires the Oracle libclntsh.so shared library. If this file is unknown to ld.so.conf, add it using the ldconfig command.
sernet.de maintain the latest Samba releases in a yum repository, allowing for an easy and painless install or upgrade of Samba on your yum based Linux distribution.
To install the latest available Samba execute the following commands at the shell:
# cd /etc/yum.repos.d # wget http://ftp.sernet.de/pub/samba/experimental/centos/5/sernet-samba.repo # yum install samba
To upgrade an existing Samba install:
# cd /etc/yum.repos.d # wget http://ftp.sernet.de/pub/samba/experimental/centos/5/sernet-samba.repo ## Note: edit sernet-samba.repo and add the line "gpgcheck=false" otherwise ## it will not install as it is not signed
# yum update samba
Note: These steps will install the very latest build available at sernet.de.
If you require a less bleeding edge version of Samba, use the "tested" repo. This can be found at the following URL: http://ftp.sernet.de/pub/samba/tested/rhel/5
This article talks about the log files available in Recital products and how to enable logging when required.
Overview
When discussing a problem with the Recital Support Team, one of the most common requests is that you enable logging and send them the log files produced. Log files along with error files are designed to provide detailed information about Recital processes and the prevailing environment and can be a fast-track to resolving a problem.
Log Files
There are three main types of log file:
- System Log
- Client/Server Communication Logs
- Custom Logs
System Log
The System log is a system-wide all product log. It tracks all login and logout operations from either Recital or the Recital Server. Logout details include the exit code: 0 for an error-free, 'normal' exit and the error number and message when an error has occurred. It also shows the licenses that have been loaded and any license error codes and messages. The system log filename is recital.log.
Client/Server Communication Logs
The Client/Server communication logs track the requests and responses between the Recital Server and its clients. The log files are as follows:
Filename | Type | Description |
---|---|---|
dbserver.log |
System-wide |
The Recital Server startup log. This logs any problems with the Recital Server startup. |
port.log |
System-wide |
The port listener log. The port listener (or portserver) listens on port 8001 for client connection requests and spawns the appropriate server process. |
net.log |
Connection |
The netserver log. The netserver is the Recital Server database and 4GL engine. |
rsi.log |
Connection |
The Recital Server Interface (RSI) Gateway log. This logs communication with the Database Gateways to SQL databases. |
rec.log |
Connection |
The Recital Database Gateway log. The Recital Database Gateway (or recserver) is the SQL database engine for Recital Gateway data access. |
mys.log |
Connection |
The MySQL Database Gateway log. |
ora.log |
Connection |
The Oracle Database Gateway log. |
inf.log |
Connection |
The Informix Database Gateway log. |
ing.log |
Connection |
The Ingres Database Gateway log. |
pos.log |
Connection |
The PostgreSQL Database Gateway log. |
jdb.log |
Connection |
The JDBC Driver Database Gateway log. |
Custom Logs
The Recital/4GL USERLOG() function can be used to log information to a user-specific log file for debugging or audit trail purposes. For full information on this function, please see the USERLOG() documentation.
Enabling Log Files
For instructions on enabling log files for individual products, please follow these links:
- Recital Server for Windows
- Recital Server for Linux
- Recital Server for UNIX
- Recital Server for OpenVMS
- Recital for Linux
- Recital for UNIX
- Recital for OpenVMS
Enabling Log Files: Recital Server for Windows
To enable the system log file for the Recital Universal Application Server for Windows, include the following command in the UAS\config.db file:
set syslogging on
The Recital Server Manager System Logging tab allows for the viewing and resetting of the System log.
Section
Item
Description
System Logging
DateTime
Date and time stamp of the action.
Name
Login name used by connection
Action
Action logged: Login, Logoff, Errot
Details
Details of action
Buttons
Purge
Allows the log file to be reset
Refresh
Refreshes the display
To set up Client/Server logging, use the Recital Server Manager Settings tab to update the server's Registry entries:
The following Log file settings can be configured:
Item |
Description |
---|---|
Log files Directory Path |
Enter the directory in which log files will be created. The default is the UAS\log directory. |
Enabled |
Check to enable log file creation. |
Versions |
Check to enable log file versioning. |
Listener |
Click to view the current port listener log file |
Server |
Click to view the current netserver log file |
Purge |
Click to purge all log files |
Enabling Log Files: Recital Server for Linux
To enable the system log file for the Recital Server for Linux, include the following command in the conf/config.db file:
set syslogging on
To set up Client/Server logging, the Recital Server can be started with the 'logging' parameter, in which case, all relevant logging will take place.
# service startup logging<
Alternatively, one or more of the following environment variables can be added to the dbserver.conf file or set at the Operating System prompt. The Recital Server must be restarted before environment variable changes will be recognized. Each environment variable should be set to the name of a log file.
Environment Variable
Logs Activity of...
UASLOG_PORT
Port Server (db_rsiserver)
UASLOG_NET
(Net) Server (db_netserver)
UASLOG_ORA
Oracle Server (db_oraserver)
UASLOG_INF
Informix Server (db_infserver)
UASLOG_ING
Ingres Server (db_ingserver)
UASLOG_JDB
JDBC Server (db_jdbserver)
UASLOG_REC
Recital Server (db_recserver)
Extract from recital.conf:
UASLOG_PORT="port.log" ; export UASLOG_PORT UASLOG_NET="net.log" ; export UASLOG_NET UASLOG_ORA="ora.log" ; export UASLOG_ORA UASLOG_INF="inf.log" ; export UASLOG_INF UASLOG_ING="ing.log" ; export UASLOG_ING UASLOG_JDB="jdb.log" ; export UASLOG_JDB UASLOG_REC="rec.log" ; export UASLOG_REC
DB_LOGDIR
If the environment variable DB_LOGDIR is set to an existing directory, all log files will be written to this directory. If not, the log files will be created in the bin directory.
DB_LOGDIR is set in the conf/recital.conf file. By default it is set to the log directory:
DB_LOGDIR=${ROI_ROOT}log/ ; export DB_LOGDIR
DB_LOGVER
If the environment variable DB_LOGVER is greater than 0, version numbers are added to the file names. For example, the activity of the first Net Server process will be logged to net.log, the second to net001.log, the third to net002.log etc. up to the maximum value of DB_LOGVER.
DB_LOGVER is set in the conf/recital.conf file:
DB_LOGVER=10; export DB_LOGVER
Enabling Log Files: Recital Server for UNIX
To enable the system log file for the Recital Server for UNIX, include the following command in the conf/config.db file:
set syslogging on
To set up Client/Server logging, the Recital Server can be started with the 'logging' parameter, in which case, all relevant logging will take place.
# service startup logging
Alternatively, one or more of the following environment variables can be added to the <em>dbserver.conf</em> file or set at the Operating System prompt. The Recital Server must be restarted before environment variable changes will be recognized. Each environment variable should be set to the name of a log file.
Environment Variable
Logs Activity of...
UASLOG_PORT
Port Server (db_rsiserver)
UASLOG_NET
(Net) Server (db_netserver)
UASLOG_ORA
Oracle Server (db_oraserver)
UASLOG_INF
Informix Server (db_infserver)
UASLOG_ING
Ingres Server (db_ingserver)
UASLOG_JDB
JDBC Server (db_jdbserver)
UASLOG_REC
Recital Server (db_recserver)
Extract from recital.conf:
UASLOG_PORT="port.log" ; export UASLOG_PORT UASLOG_NET="net.log" ; export UASLOG_NET UASLOG_ORA="ora.log" ; export UASLOG_ORA UASLOG_INF="inf.log" ; export UASLOG_INF UASLOG_ING="ing.log" ; export UASLOG_ING UASLOG_JDB="jdb.log" ; export UASLOG_JDB UASLOG_REC="rec.log" ; export UASLOG_REC
DB_LOGDIR
If the environment variable DB_LOGDIR is set to an existing directory, all log files will be written to this directory. If not, the log files will be created in the bin directory.
DB_LOGDIR is set in the conf/recital.conf file. By default it is set to the log directory:
DB_LOGDIR=${DB_ROOT}log/ ; export DB_LOGDIR
DB_LOGVER
If the environment variable DB_LOGVER is greater than 0, version numbers are added to the file names. For example, the activity of the first Net Server process will be logged to net.log, the second to net001.log, the third to net002.log etc. up to the maximum value of DB_LOGVER.
DB_LOGVER is set in the conf/recital.conf file:
DB_LOGVER=10; export DB_LOGVER
Enabling Log Files: Recital Universal Application Server for OpenVMS
To enable the system log file for the Recital Universal Application Server for OpenVMS, include the following command in the db_uas:config.db file:
set syslogging on
To set up Client/Server logging, one or more of the following symbols can be added to the <em>db_uas:login.com</em> file. The Recital Server must be restarted before symbol changes will be recognized. Each symbol should be set to the name of a log file.
Symbol
Logs Activity of…
UASLOG_PORT
Port Server (db_rsiserver)
UASLOG_NET
(Net) Server (db_netserver)
UASLOG_ORA
Oracle Server (db_oraserver)
UASLOG_INF
Informix Server (db_infserver)
UASLOG_ING
Ingres Server (db_ingserver)
UASLOG_JDB
JDBC Server (db_jdbserver)
UASLOG_REC
Recital Server (db_recserver)
Extract from db_uas:login.com
$ uaslog_port :== port.log $ uaslog_net :== net.log $ uaslog_ora :== ora.log $ uaslog_inf :== inf.log $ uaslog_ing :== ing.log $ uaslog_jdb :== jdb.log $ uaslog_rec :== rec.log
DB_LOGDIR
If the symbol DB_LOGDIR is set to an existing directory, all log files will be written to this directory. If not, the log files will be created in the UAS directory.
DB_LOGDIR is set in the db_uas:login.com file. By default it is set to the UAS.log] directory:
$db_logdir :== 'db_root'.log] ! system logging directory
DB_LOGVER
If the symbol DB_LOGVER is enabled, version numbers are added to the file names. For example, the activity of the first Net Server process will be logged to net.log, the second to net001.log, the third to net002.log etc.
DB_LOGVER is set in the db_uas:login.com file:
$db_logver :== true ! enable multiple log files
Enabling Log Files: Recital for Linux
To enable the system log file for Recital for Linux, include the following command in the conf/config.db file:
set syslogging on
Enabling Log Files: Recital for UNIX
To enable the system log file for Recital for UNIX, include the following command in the conf/config.db file:
set syslogging on
Enabling Log Files: Recital for OpenVMS
To enable the system log file for Recital for OpenVMS, include the following command in the db_ovd:config.db file:
set syslogging on
In Brief
- Log files provide important information to aid problem resolution, but they are also an overhead, so logging should only be enabled when required, not in normal production operation.
- The System log provides a system-wide view of logins, exits and error codes.
- The System log can be viewed in table format via the SYSLOGGING System Table.
- The System log is enabled using the SET SYSLOGGING ON Recital/4GL command in the conf/config.db file.
- Client/Server logs provide detailed information on client/server requests and responses.
- Client/Server logs are enabled using environment variables, symbols or Registry entries or by specifying the 'logging' parameter when starting the Recital Server.
- The location of log files is determined by the DB_LOGDIR setting.
- Versioning of log files is determined by the DB_LOGVER setting.
The following example connects to a Recital ODBC datasource, executes a query then outputs all the results from the resultset.
<?php
$sql = "select country from customers limit 10";
$conn = odbc_connect('Recital ODBC test', '?', '?');
$rs = odbc_exec($conn, $sql);
odbc_result_all($rs);
odbc_close($conn);
?>
Output:
<table><tr><th>Country</th></tr>
<tr><td>Germany </td></tr>
<tr><td>Mexico </td></tr>
<tr><td>Mexico </td></tr>
<tr><td>UK </td></tr>
<tr><td>Sweden </td></tr>
<tr><td>Germany </td></tr>
<tr><td>France </td></tr>
<tr><td>Spain </td></tr>
<tr><td>France </td></tr>
<tr><td>Canada </td></tr>
</table>
For information on installing and configuring the Recital Universal ODBC Driver and creating and modifying datasources, please see the Documentation section of this web site.
Note: Use of ? for the username and password on the local server is dependent on DB_LOCAL_LOGIN being enabled.
For systems that do not have the xterm libraries installed, please install these to use xterm, or set the DB_TERM environment variable to start Recital from a terminal:
DB_TERM=gnome-terminal; export DB_TERM
This setting can be added to the /opt/recital/conf/recital.conf (text) file to make it available system-wide.
Please note that the Recital ODBC Driver for Linux requires a 32 bit ODBC Driver Manager.
Centos 6:
sudo yum install zlib-devel.i686 pam-devel.i686(and accept dependencies)
Then run the installer in text mode
sudo ./recital-10.0.3-linux32.bin --mode textRun Recital with sudo the first time, to set the system filetype compatiblity settings.
sudo recitalAfter saving the compatibility settings, quit to exit, then run Recital as your preferred user.
> quit
$ recital
RedHat / Fedora family:
sudo yum install zlib-devel.i686 pam.i686(and accept dependencies)
Then run the installer in text mode
sudo ./recital-10.0.3-linux32.bin --mode textRun Recital with sudo the first time, to set the system filetype compatiblity settings.
sudo recitalAfter saving the compatibility settings, quit to exit, then run Recital as your preferred user.
> quit
$ recital
Ubuntu family:
sudo apt-get install ia32-libsIn later versions of Ubuntu, ia32-libs is obsolete. The following package should be installed:
sudo apt-get install lib32z1Ubuntu 12.04 and above also require the following:
sudo apt-get install libpam0g:i386Then run the installer in text mode
sudo ./recital-10.0.3-linux32.bin --mode textRun Recital with sudo the first time, to set the system filetype compatiblity settings.
sudo recitalAfter saving the compatibility settings, quit to exit, then run Recital as your preferred user.
> quit
$ recital