Re: informix upward compatibility

> I've just taken on a client who has a 4GL runtime license version 1.10 > I'd like to upgrade them to 4.0 if his existing code will run in the > 4.0 environment. > Does anyone have any knowledge of the upgradability of the 1.10 code? > I'd like to avoid re-compiling everything if at all possible.... > Your thoughts and comments are solicited and appreciated. We have converted quite a bit of code from version 1.10 on an Intel 320 running Xenix to 4.0 on our 3B2 running SystemV 3.2.3. There were very few problems. The code itself is identical. Version 4.0 and above just add a few more statements. There were a few wierd bugs though. In a MESSAGE, PROMPT, or DISPLAY do not use the CLIPPED option for some reason this causing the CLIPPED item to be doubled likelike thisthis. You can get around it by clipping the item into a string and than using the string with your MESSAGE. Certain keywords that have short names as well, such as ESCAPE, generate a syntax error unless the short form, ie ESC, is used. The query optimizer has changed in 4.0, queries that where quite fast under the 1.10 release are terribly slow under 4.0. We found this to be particularly true with the use of VIEWs. It seems that under 4.0 a VIEW causes the SQL engine to perform the table join every time it is accessed, very slow. We replaced the VIEWs with a join into a TEMP table which works quite well. Let me know if you have any particular questions. I still have access to both developement platforms. ----------------------------------------------------------------------------- Bob Kane Internet: bob@worms-emh2.army.mil (IP 134.235.9.2) TechDyn Systems Voice: (049) 6241-75936 (WORMS, GERMANY) CMR 421, BOX 706 Fax: (049) 6241-74530 APO AE 09056 CIS: 71054,2661