I have a Python application residing on Ubuntu Server 14.04.04 x86 that connects via ODBC to an iSeries (AS400) instance for reading data. This application has been in production on the same server for almost a year and everything has worked great.
Last week, for whatever reason, the SQL queries became slow to the point where the application was unusable. For testing purposes I configured a Windows 7 pc with the iSeries ODBC connection and copied over the application files. The application runs flawlessly and the SQL queries are executing quickly without any issues. I have since built a new Ubuntu server instance and have configured everything accordingly. On the new Ubuntu instance, the queries are still slow however, the queries on the Windows box are running like they should.
Can anyone shed some light as to what would cause the sudden slow down in query execution time using the Linux based ODBC connection?
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I've successfully installed the Pervasive 13's 64bit Client onto Ubuntu Server 18.04.
How can I now establish a connection to the Pervasive 13 server (which is installed on a Windows 2008 R2 server) and perform a sql query?
I'm extremely confused by the documentation, which directs me to the bcfg tool after client installation. I'm not clear if that tool is for configuring the server or for setting up the client connection. Ether way, the documentation is too abstract for my comprehension; I need concrete examples of someone successfully establishing a connection to (at least a hypothetical Pervasive server located at some hypothetical ip address) and NOT JUST abstract syntax that never shows an example of SQL statement being submitted from command line Linux.
Seriously, the documentation covers so much detail of stuff I don't immediately care about, that I can never seem to figure out my practical needs which are to simply establish a connection to the database, perform a SQL query, and get a result set.
The installation of the client should have sensible defaults, and the documentation, after installation, should focus on getting you connected and running sql statements as quickly as possible, instead of going on and on about details that are only of interest if the defaults aren't sensible. Let me connect first! Then if I have a problem, only then do I care to learn further detail about other aspects of configuring the connection.
Pervasive is such an obscure database server, that I'm left with only this documentation to figure this out. Any other database would probably have YouTube videos that show you how to install the client, and start making some SQL queries and getting result sets.
Someone at Actian, ought to be kind enough to make a quick start video for the client on Ubuntu Server that quickly covers installation and finishes where you're submitting sql queries and get result sets. After all, that's the purpose of database client.
Can someone please provide some concrete examples of how I can turn this successful installation into a relationship with the database server where I can submit SQL queries and receive result sets?
I'm not sure why the documentation points to bcfg.
If the Client is installed and didn't display any errors, you need to add an ODBC DSN using dsnadd (https://docs.actian.com/psql/PSQLv13/index.html#page/uguide%2Fuguide.dsnadd.htm%23ww68699). An example of creating a client side DSN pointing to a remote database is:
dsnadd -dsn=clientDemodata -db=Demodata -host=WindowsServerName
(where clientDemodata is the DSN created on the Linux box, Demodata is the PSQL database on the remote server called WindowsServerName).
Once the DSN has been added, you should be able to use isql or isql64 (https://docs.actian.com/psql/PSQLv13/index.html#page/uguide%2Fuguide.isql.htm%23ww138933) to execute a query.
Running isql / isql64 with just the DSN will let you execute SQL queries interactively:
isql64 clientDemodata
An example of running isql using a file as input for the SQL statement(s) is:
cat two-queries.sql | isql clientDemodata -b
If you've done all that, what errors or behavior are you seeing?
My working system is Centos7. Now I'am develop a web application, it use Oracle Database. So I use instantclient 11.2 to connect the Oracle on my Centos7, it use long time to connect! Although connect successful, but I have to wait for at least 3 minute! The web application startup will init the datasource, for each datasource, it also use at least 3 minute to finish! How odd that my colleague connect or init datasource is really quick by use Windows OS(only I use linux)! The database installed at the linux server(also Centos7). we all use the same network environment! How can I fix this problem? I love Linux so much that I don't want to change to Windows for working! Thank for helping me to solve this problem!(I am so sorry that my English is very bad )
I poll a Windows Server's ODBC database every 10 minutes from a Linux server. Whether or not the Windows program that updates the database is running, I obviously can get data - old data - back from the database.
But I need to be sure that the remote Windows application is actually running and updating the database.
How can I query the remote Windows server to see if the specific program is active?
You should be able to get the information you need via WMI, which linux can query with special packages. the WMI namespace you need will be Win32_process, which will return a collection of process data, from there you can parse the data and work out if your app is running or not. I've linked a linux wmi client below.
https://www.krenger.ch/blog/wmi-commands-from-linux/
I'm writing a small program in Free Pascal on Linux and connecting to a Firebird database on the same server. For testing, I initially wrote a console application using the TIBConnection components in FP and successfully connected to the Firebird database and listed records from one of the tables.
Now I'm wanting to do the same thing from a CGI application under Apache. A sample CGI app with various parameters displays different HTML results via the WebBroker "actions" like expected.
So both preliminary tests, connecting to Firebird and getting a CGI web app running, have worked. The final test is to combine them and that's where my problem is.
Whenever I run the test cgi application and try to connect to the Firebird database, I get a "permission denied" error. I've left the username, password, and port all at defaults, have checked the firewall, switched between "localhost" and "127.0.0.1" and several other things including setting the permissions on the database file to read/write globally (for temporary testing, of course).
I've found lots of information on the internet about connecting to Firebird on Linux and lots of information about writing CGI applications, but very little where it combines the two subjects. I'm sure there's a subtle yet important security or firewall issue, but it eludes me.
CentOS 6.6 64-bit on a virtual machine
Firebird 2.1.7 64-bit
Lazarus 1.4.0 64-bit
Anyone have any suggestions on what I could try?
I figured out how to get it working by reading the solution to a different problem. Not sure why disabling the firewall didn't work (I had to completely uninstall it) and don't know what SELinux is yet (had to set it to "permissive"), but I will need to study those two issues so the live server won't be left vulnerable.
Here is the problem: We have a client that uses Progress Openedge database, we need to execute queries on this database from our servers.
Currently the drivers are installed on our Windows server, and the PHP code uses ODBC to run the queries.
Now we would like to move the code to a Linux server. We tried before to work with their linux drivers but that attempt has failed.
The question is, Is it possible somehow to run PHP code on a linux server, this code communicates with the Windows server, runs the query on the Windows server, and return the results to Linux?
How would you access to this problem.
Thanks!
Yes, it's possible. Your question boils down to "how can my Linux server ask my Windows server to do something" (where the "something" happens to be "talk to a database"), and there are a variety of ways to accomplish that. You could run a web service (RESTful or SOAP) on the Windows server, for example.
Make sure you think about security: if you deploy a service on your Windows server that lets remote clients modify a database, you have to be mindful of which remote clients are allowed to use that service. The last thing you want to do is accidentally allow random strangers to run arbitrary queries against your database.
We have a Knowledgebase Article detailing some setup procedures for Linux installations; it also has a video explaining some aspects of the setup. If the other answered haven't provided a complete solution for you, hopefully our article can at least get you started in the right direction.
Also keep in mind that depending on your version of OE, the driver libraries may be different.