Test Drive of Linkway
Shawn M. Gordon
What it can do?
Distributed access to data is a hot topic, and it’s only getting hotter. You see distributed applications and client/server model computing becoming more and more prevalent, and you want to get in the game. A good generic way to leverage your HP 3000 into this is by using an ODBC driver. ODBC is a Microsoft brainchild that stands for Open DataBase Connectivity. This protocol allows you to select a driver, use a generic data access syntax, and read/write from the database at the other end. The trick in the 3000 market was getting something to read and write to an Image/SQL database.
HP offered a free 16 bit ODBC driver years ago, but never got around to doing a 32 bit driver until recently. CSL has been offering either a 16 or 32 bit driver since 1995. Essentially you can take any MS Windows based program that supports ODBC such as Word, Excel, Access, Visual Basic, etc., and set it up to get it’s data straight from your Image/SQL database. The magic on your end is in setting up the SQL part of Image/SQL, but that is beyond the scope of this review.
Linkway is also pretty unique in that it doesn’t rely on only a tcp/ip connection to the host, which is what is standard products use. Linkway also supports Serial, which includes dial up, and X25 connections.
How does it work?
There are two basic components involved here, the server side software that runs on the HP 3000, this process is typically known as a “listener” because it listens for client requests. The client software is the second component. This ODBC driver needs to be installed on each client PC that wishes to take advantage of the Linkway driver. It’s this piece of software that act’s as the generic middleware between the client and the server. Your VB application doesn’t need to know it’s an Image database on a serial connection, it’s all handled inside the ODBC driver itself.
On the server side of the process there are a number of things to occupy your time, but let’s talk about the features. Once your server is running you have a utility that allows you to monitor and manipulate the server process, this program is called LINKCTL and you can see the dialog in Figure 1.
By building a message file called LINKLOG in the same group and account where there LINKWAY server is running you are able to have a comma delimited log file generated, see Figure 2 for an example and explanation of the fields. Since the file is comma delimited you should be able to import it into any tool you wish to generate custom reports.
By building a message file name LINKMON using the same rules, you will get a log of all SQL information. See Figure 3 for an example of the file and description of the layout.
Linkway will also tie into Security/3000 from VESOFT if you own it, and make use of the HELLO procedure exits. This allows you to apply the same granular security to the ODBC connections as you do to your regular user logons. This was a nice, and unexpected feature.
Some features specific to ODBC are support for Multi-Tables in a single SELECT statement. Multi-Data source is supported. Support for Microsoft Query97, which is used by Excel and Word for extracting data from databases. Unique keys is a big problem that most users run into when attaching to an Image detail data set. Linkway get’s around this by allowing you to define a multi-column key which would provide a unique value.
Numeric scaling, this provides for server side manipulation of integer type data so that only the result is brought down and translated by the client. The 3000 internal representation of integers is different than how Windows handles it, so translation has to happen somewhere, this process is the most efficient way to handle it.
The list of features goes on and on, CSL is to be complimented for the completeness of their product, and the thought to maintaining industry standards while taking care to support our beloved HP 3000 architecture.
Installation and Documentation
I was able to get the whole installation off of the Internet, which was quit convenient. You unzip some files, and then upload a couple of job streams, stream them, then upload the binary files and stream another job which converts them to standard HP program files. I had a little trouble with this process because of the way Reflection was defaulting the binary files. Once I used FTP everything worked fine. CSL was very helpful in this process and went out of their way to make themselves available even with the dramatic time difference.
The documentation doesn’t waste any time getting down to business, they go through the install and then start you right off doing samples. Unfortunately there didn’t seem to be just a straight forward tutorial guide so I got a bit stuck getting started. The appendices are very good however, and you get a complete description of every file that is part of the distribution.
It’s a bit of a trick getting all the components set up and going, but once you do it’s pretty nifty. I got the Linkway server running, and used the SQL Explorer program that comes with Delphi 3 from Borland, to open and view the tables. I went ahead and just used the sample table supplied from CSL, and if you take a look at Figure 4 you will see how all aspects of the DBE is available in the left pane, and the data in the highlighted table is shown in the right pane. When I connected to the ODBC source I got the Linkway banner, so I knew it was going to the right place. The response was pretty much instant, so I have a warm fuzzy on the OCBD driver implementation.
As mentioned earlier, you can use multiple connection types, serial, network, X.25, dialup. Take a look a figure 5 for an example of how the configuration screen looks. Basically you can set up an ODBC source for any connection type that you are interested in, and then toggle back and forth between them. This is handy if you are a road warrior with a dockable laptop and need to quickly and easily switch between serial and network connections.
The dial up connection option is a bit more complex to set up, but CSL is right there ready to help you get it done right. I was very happy with the quality of their support.
Linkway is certainly a robust product, offering a wealth of connection and client operating system options. Make no mistake, any ODBC product takes a fair amount of thought and effort to set up, configure and maintain. The payoff could be tremendous for you, especially if you want to give end user’s generic reporting tools such as Crystal Reports or R&R and let them go after your database. Keep in mind that while ODBC supports SQL syntax, and ALLBASE translates this as best it can for Image, but if someone does a wild card search on CUST-NAME for example, you are going to have a serial read. So careful thought needs to go into each project.
Linkway version A.01.00
Computing Solutions Limited
10 St. Andrews Rd
Droitwich, Worcestershire, UK WR9 8DN
Phone 44 1905 794 400
FAX 44 1905 794 464
Linkway includes the 3000 based server software and the ODBC driver that is required for the client PCs. It provides 16 and 32 bit ODBC driver support from Win 3.1, Win 95, and Win NT applications. Linkway supports Serial, Remote, and X25 connections in addtion to standard LAN connectivity. Enhanced security features are supported through Security/3000 by VESOFT.
Linkway for the HP 3000 runs on all HP 3000 Series 900s, MPE/iX 4.0 or later. The software is tier and user based ranging from $2,500 for 8 users on a 918 to $20,000 for an unlimited license on a 996. Discounting on multiple CPUs. Support is 20% of the purchase price per year and includes phone in, electronic support and new releases of the software. All prices are in US dollars.
Figure 1 linkctl Computing Solutions (c) 1997 LINKCTL Version 18.104.22.168 Inet 198.246.183.001 Service 9000 Valid controls are : <[>'?' or 'HELP' for this screen] TERMINATE : Terminate the CSL Server KILL 999 : Kill a CSL Server Son which has PIN no. 999 STOP : Kill all sons and terminate the CSL server SONS : List active Server Son PIN numbers PORT 9999 : Change the Sockets Service (Port) No. from 9000 SERVER USER.ACCOUNT,GROUP : Change the Sockets Service to that for this user CONFIG FILENAME.GROUP.ACCOUNT : Use alternate configuration file from LINKSRV.LINKWAY.CSL for networked HP3000's <[>Applies to LINKCTL only] EXIT or QUIT : End this program Please enter command : Figure 2 DUB750U,KENS,USER,CLIENTS,DATABASE,Start,1997-02-04,16:38:03,0,End,1997-02-04,16:43:29,0,CPU,17684,MSACCESS.EXE DUB756U,KENS,USER,CLIENTS,DATABASE,Start,1997-02-04,16:38:02,0,End,1997-02-04,16:43:30,0,CPU,1863,Server DUB750U,KENS,DATABASE,ADEV,DATABASE,Start,1997-02-04,18:34:30,0,End,1997-02-04,18:46:36,0,CPU,417,ODBCTEST.EXE DUB756U,KENS,DATABASE,ADEV,DATABASE,Start,1997-02-04,18:34:29,0,End,1997-02-04,18:46:37,0,CPU,1083,Server DUB750U,ROB,MGR,SOUTH,DATABASE,Start,1997-02-05,12:42:30,0,End,1997-02-05,13:56:51,0,CPU,66934,MSACCESS.EXE DUB756U,ROB,MGR,SOUTH,DATABASE,Start,1997-02-05,12:42:28,0,End,1997-02-05,13:56:53,0,CPU,3026,Server The columns are as follows : 1. Server program ID:
or for CSL information only 2. HPJOBNAME, 3. HPUSER, 4. HPACCOUNT, 5. HPGROUP, 6. Start date as CCYY-MM-DD Start time as HH:MM:SS Start time daylight saving flag 0 - FALSE 1 - TRUE 7. End date as CCYY-MM-DD End time as HH:MM:SS End time daylight saving flag 0 - FALSE 1 - TRUE 8. CPU time used on the HP3000 in milliseconds. 9. PC application program or Figure 3 DUB750U,CSLKEN,DATABASE,ADEV,DATABASE,Start,1997-07-25,18:13:49.809,1,Profile,1997-07-25,18:13:50.742,1,CPU,675,MSACCESS.EXE DUB750U,CSLKEN,DATABASE,ADEV,DATABASE,Start,1997-07-25,18:13:49.809,1,Profile,1997-07-25,18:13:50.742,1,CPU,675,MSACCESS.EXE **************30**** DUB750U,CSLKEN,DATABASE,ADEV,DATABASE,Start,1997-07-25,18:13:49.809,1,Select,1997-07-25,18:13:52.642,1,CPU,1109,MSACCESS.EXE SELECT Config, nValue FROM MSysConf; DUB750U,CSLKEN,DATABASE,ADEV,DATABASE,Start,1997-07-25,18:13:49.809,1,Parameters,1997-07-25,18:13:52.724,1,CPU,1140,MSACCESS.EXE Parms<:f160,B Arial Narrow,> : DUB750U,CSLKEN,DATABASE,ADEV,DATABASE,Start,1997-07-25,18:13:49.809,1,End,1997-0 7-07-25,18:13:53.184,1,CPU,1467,MSACCESS.EX The entries are : 1. Server program ID: for CSL information only 2. HPJOBNAME 3. HPUSER 4. HPACCOUNT 5. HPGROUP 6. Start date as CCYY-MM-DD Start time as HH:MM:SS Start time daylight saving flag 0 - FALSE 1 - TRUE 7. Command type or Profile or End. End date as CCYY-MM-DD End time as HH:MM:SS End time daylight saving flag 0 - FALSE 1 - TRUE 8. CPU time used on the HP3000 in milliseconds. 9. PC application program