Here's how to set up field validation for a field with a small static number of acceptable values.
Using the example.dbf table from the southwind sample database, validation can be added to the title field to ensure it matches one of a list values.
open database southwindThe inlist() function checks whether the specified expression exists in the comma-separated list which follows. An attempt to update title with a value not in the list will give an error: Validation on field 'TITLE' failed.
alter table example add constraint;
(title set check inlist(alltrim(title),"Miss","Mr","Mrs","Ms"))
If you have access to the Recital Workbench, you can use the modify structure worksurface to add and alter your dictionary entries, including a customized error message if required.
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sudo apt-get install ia32-libsIn later versions of Ubuntu, ia32-libs is obsolete.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
If you want details about how storage devices are performing on Redhat/Centos/Fedora use the vmstat and iostat commands.
After installing Centos 5.3 the iostat command is not available. To install it use yum:
# yum install sysstat
In this article Barry Mavin, CEO and Chief Software Architect for Recital provides details on how the Recital Database Server can be used to provide a solution for Universal Data Integration.
Overview
The Recital Database Server handles universal cross-platform data access to a wide range of data sources. The database server natively handles full remote SQL data access to Recital, Visual FoxPro, FoxPro, FoxBASE, Clipper and older dBase data. Using Bridges, it handles full remote SQL data access to C-ISAM and OpenVMS RMS. Using gateway connections, it handles full remote SQL data access to Oracle, MySQL, PostgreSQL, SQL Server, server-side ODBC, server-side JDBC and server-side OLE DB data sources. With its ability to access data using server-side ODBC, JDBC and OLE DB drivers from clients on all supported operating systems (Windows, Linux, Unix, OpenVMS), the Recital Database Server is an ideal Data Integration Solution for applications of all sizes and complexity.
Universal Data Integration Solutions
There are several ways in which data may be accessed by the Database Server.
Table 1:
Client Universal Data Access solutions for accessing local or remote data.
| Client | Solution |
|---|---|
| Recital | Use remote gateway connections |
| Visual FoxPro | Use the Universal ODBC Driver |
| Java (all platforms) | Use the Universal JDBC Driver |
| .NET Framework | Use the Universal .NET Data Provider |
| Microsoft Office | Use the Universal ODBC Driver |
| Windows Mobile | Use the Universal Compact Framework .NET Data Provider |
| PHP on Linux | Use the Universal ODBC Driver for Linux |
| Mono on Linux | Use the Universal .NET Data Provider |
| Others | If the data source you want to access is not in the list above, then you can use a remote ODBC, JDBC or OLE DB gateway. You can find examples of connection strings for most ODBC and OLE DB data sources by clicking here. |
Table 2:
Windows Server Universal Data Access solutions accessible from any remote client running on Windows, Linux, Unix or OpenVMS:
| Data Source | Solution |
|---|---|
| Recital | Native support (See table 1) |
| Visual FoxPro | Native support (See table 1) |
| FoxPro | Native support (See table 1) |
| FoxBASE | Native support (See table 1) |
| Clipper | Native support (See table 1) |
| dBase | Native support (See table 1) |
| C-ISAM | Use a bridge (See table 1) |
| Access | Use a gateway connection gateway="oledb:Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\somepath\mydb.mdb;User Id=admin;Password=;" |
| Exchange | Use a gateway connection gateway="oledb:Provider=ExOLEDB.DataSource;Data Source=http://servername/publicstore" |
| Excel | Use a gateway connection gateway="oledb:Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\MyExcel.xls;" |
| Oracle | Use a gateway connection gateway="oledb:Provider=msdaora;Data Source=TheOracleDB;User Id=xxxxx;Password=xxxxx;" |
| SQL Server | Use a gateway connection gateway="oledb:Provider=sqloledb;Data Source=Aron1;Initial Catalog=pubs;User Id=sa;Password=asdasd;" |
| MySQL | Use a gateway connection gateway="oledb:Provider=MySQLProv;Data Source=mydb;User Id=xxxxx;Password=xxxxx;" |
| IBM DB2 | Use a gateway connection gateway="oledb:Provider=DB2OLEDB;Network Transport Library=TCPIP;Network Address=XXX.XXX.XXX.XXX;Initial Catalog=MyCtlg;Package Collection=MyPkgCol;Default Schema=Schema;User ID=MyUser;Password=MyPW" |
| Sybase ASA | Use a gateway connection gateway="oledb:Provider=ASAProv;Data source=myASA" |
| Sybase ASE | Use a gateway connection gateway="oledb:Provider=Sybase.ASEOLEDBProvider;Srvr=myASEserver,5000;Catalog=myDBname;User Id=username;Password=password" |
| IBM Informix | Use a gateway connection gateway="oledb:Provider=Ifxoledbc.2;password=myPw;User ID=myUser;Data Source=dbName@serverName;Persist Security Info=true" |
| Ingres | Use a gateway connection gateway="odbc:dsn=data_source_name" |
| Firebird | Use a gateway connection gateway="odbc:dsn=data_source_name" |
| IBM AS400 iSeries | Use a gateway connection gateway="oledb:PROVIDER=IBMDA400; DATA SOURCE=MY_SYSTEM_NAME;USER ID=myUserName;PASSWORD=myPwd" |
| Interbase | Use a gateway connection gateway="oledb:provider=sibprovider;location=localhost:;data source=c:\databases\gdbs\mygdb.gdb;user id=xxxxx;password=xxxxx" |
| Others |
If the data source you want to access is not in the list above, then you can use server-side ODBC, JDBC or OLE DB. |
Table 3:
Linux and Unix Server Universal Data Access solutions accessible from any remote client running on Windows, Linux, Unix or OpenVMS:
| Data Source | Solution |
|---|---|
| Recital | Native support (See table 1) |
| Visual FoxPro | Native support (See table 1) |
| FoxPro | Native support (See table 1) |
| FoxBASE | Native support (See table 1) |
| Clipper | Native support (See table 1) |
| dBase | Native support (See table 1) |
| C-ISAM | Use a bridge (See table 1) |
| Oracle | Use a gateway connection gateway="oracle:Connection_String" |
| MySQL | Use a gateway connection gateway="mysql:Connection_String" |
| IBM DB2 | Use a gateway connection gateway="db2:Connection_String" |
| PostgreSQL | Use a gateway connection gateway="postgres:Connection_String" |
| Others |
If the data source you want to access is not in the list above, then you can use a server-side JDBC driver. |
Table 4:
OpenVMS Server Universal Data Access solutions accessible from any remote client running on Windows, Linux, Unix or OpenVMS:
| Data Source | Solution |
|---|---|
| Recital | Native support (See table 1) |
| Visual FoxPro | Native support (See table 1) |
| FoxPro | Native support (See table 1) |
| FoxBASE | Native support (See table 1) |
| Clipper | Native support (See table 1) |
| dBase | Native support (See table 1) |
| RMS | Use a bridge (See table 1) |
| Others |
If the data source you want to access is not in the list above, then you can use a server-side JDBC driver. |
Supported Data Sources
Native Data Access
The Recital Database Server has native built-in support for the following data sources:
- Recital
- Visual FoxPro
- FoxPro
- FoxBASE
- Clipper
- dBase
You can setup tables to work with using the Database Administration Tool in Recital Enterprise Studio.
Bridges
Using Bridges, you can access the following data sources as if they were standard Recital/FoxPro tables:
- CISAM
- OpenVMS RMS
You can setup bridges using the Database Administration Tool in Recital Enterprise Studio.
Gateways/Connections
Using Gateways, you can transparently access the following local or remote data sources:
- Recital
- Oracle
- ODBC (Server-side ODBC data sources)
- JDBC (Server-side JDBC data sources)
- OLEDB Use this to connect to SQL Server and other Windows OLE DB data sources)
- MySQL
- PostgreSQL
Remote Data Object functions
Recital 10 includes a complete and robust set of data source independent functions for accession MySQL, Oracle, DB2 and Postgres. This article explains how to use them.
Client Data Access drivers
Included with the Recital Database Server are three Client drivers. These Client drivers can access any data sources supported by the Recital Database Server. They are not restricted to accessing only Recital data. They can be used to access server-side ODBC, JDBC and OLE DB data sources also.
Recital Universal .NET Data Provider
Use this client driver when building .NET applications with Visual Studio .NET. A data provider in the .NET Framework serves as a bridge between an application and a data source. A data provider is used to retrieve data from a data source and to reconcile changes to that data back to the data source.
Key features of the Recital Universal .NET Data Provider:
- Fully Internet enabled
The Recital Universal .NET Data Provider works across the internet providing access to a wide range of data sources located on remote servers running Windows, Linux, Unix and OpenVMS. - SQL Server compatible
The Recital Universal .NET Data Provider is plug compatible with the .NET Framework SQL Server Data Provider. - Cross-platform Data Integration
Using the Recital Universal .NET Data Provider, you can connect to remote Windows, Linux, Unix or OpenVMS servers and access any data source supported by the Recital Database Server. - Managed code
The Recital Universal .NET Data Adaptor written in C# is 100% .NET Framework managed code. - Runs on Windows Mobile
The Recital Universal .NET Data Adaptor runs under the .NET Compact Framework on Windows Mobile.
Recital Universal JDBC Driver
The JDBC API is the industry standard for database-independent connectivity between the Java programming language and a wide range of databases. The JDBC API provides a call-level API for SQL-based database access. JDBC technology allows you to use the Java programming language to exploit "Write Once, Run Anywhere" capabilities for applications that require access to enterprise data.
Key features of the Recital Universal JDBC Driver:
- Fully Internet enabled
The Recital Universal JDBC driver works across the internet providing access to a wide range of data sources located on remote servers running Windows, Linux, Unix and OpenVMS. - JDBC 3.0 API
The Recital Universal JDBC driver supports the JDBC 3.0 API. - Pure Java Type 3 Driver
The Recital Universal JDBC driver is a 100% pure Java Type 3 driver. - Full Access to Metadata
The JDBC API provides metadata access that enables the development of sophisticated applications that need to understand the underlying facilities and capabilities of a specific database connection. - Cross-platform Data Integration
Using the Recital Universal JDBC driver, you can connect to remote Windows, Linux, Unix or OpenVMS servers and access any data source supported by the Recital Database Server. - No Installation
A pure JDBC technology-based driver does not require special installation; it is automatically downloaded as part of the applet that makes the JDBC calls. The Recital Universal JDBC Driver is 100% java.
Recital Universal ODBC Driver
Connect to remote data from Microsoft Office or other applications that support ODBC data access. The Recital Universal ODBC Driver is also available for Linux and Unix.
Key features of the Recital Universal ODBC Driver:
- Fully Internet enabled
The Recital Universal ODBC driver works across the internet providing access to a wide range of data sources located on remote servers running Windows, Linux, Unix and OpenVMS. - Works with Crystal Reports
The Recital Universal ODBC driver supports the SQL syntax generated by Crystal Reports. - Works with Microsoft Office
The Recital Universal ODBC driver works with Microsoft Office products. - Works with PHP on Linux
The Recital Universal ODBC driver is available for Linux and works with PHP.
When installing nomachine on redhat 5.3 64-bit be sure to:
- Make sure you have installed the 64-bit packages as the 32-bit ones will not work.
- add the hostname to /etc/hosts
- Check "Disable encryption of all traffic" (in configuration / advanced tab)
- add the hostname to /etc/hosts
- make sure the host IP is not specified as 127.0.0.1 line
- Uncheck "Disable encryption of all traffic" (in configuration / advanced tab)
Ext3 commits writes to disk within approximately 5 seconds - Ext4 can take from 40-150 seconds. In addition, if a system is using Ext3 and crashes before the commit takes place you will still have the previous contents of a file where under Ext4 the file will be empty. Theodore Tso feels that this is a failure at the application level and that the file system is behaving as designed and as specified by the POSIX spec (which apparently does not specify what is supposed to happen when a system is not shut down cleanly). His solution to the issue is to suggest proper use of fsync() and lists various scenarios/examples in post 54 of the bug report (linked above). In addition he wrote a patch that recognize the rename() situation mentioned in his post 54 yet retains the normal Ext4 behaviors and performance in the majority of cases. Also a more "proper" solution has been provided which allows the behavior of Ext3 to be retained under Ext4 by mounting it with alloc_on_commit.
A somewhat related topic is the use of on-board caching by hard drives. This behavior can be modified on most drives by using hdparm.
Latest Development News
The Lianja Application Platform is a cost-effective cloud database computing platform for SMEs (Small and Medium-sized Enterprises) that lets them focus on developing and deploying business Apps without the need to invest in lengthy application development times and an expensive IT infrastructure.The three pillars of Lianja are:
- The Lianja App Builder
- The Lianja Cloud Database
- Lianja.com Apps
I am pleased to finally report that the Centos release of Redhats 5.3 has been built and is available for download from http://www.centos.org/
The highlights of this release can be found at the following URL: http://www.redhat.com
The main areas of interest in my opinion excluding critical secirty fixes are:
- Updated hardwaresupport support for the new Intel Core i7 (Nehalem) chips
- Beefed up virtualiseation support increasing CPU and Ram limits of Virtual machines.
- Inclusion of the fully open sourced OpenJDK. This makes Red Hat Enterprise Linux 5.3 the first enterprise-ready solution with a fully open source Java stack when combined with JBoss Enterprise Application Platform.
For those who already have Centos 5.2 installed you can simply receive the update via Yum.
Before you do the following, check that you do not have 3rd party repo's and the Centos-testing repo enabled.
You can display the currently enabled repo's using the following command.
$ yum repolist
Then as root at the prompt type:
$ yum update