Bug with LVARCHAR columns in Informix

Hello, I just detected a bug in displaying large LVARCHAR column values from Informix tables. I used this column type several times before without this error, but now for the first time I have really long strings. I have a table with a column of type LVARCHAR(2048) which is the maximum length for this type. In the data tab of the table view as well as in the SQL Commander I get null values for this column (with a red background) and an error icon at the bottom of the display. Clicking the error icon results in the error message: "Error getting value for: 36/1: java.sql.SQLException: Encoding or code set not supported.". I then tried in an SQL Commander tab to get substring from tthis column. This worked until the length of 1026. All higher lengths result in the same error as the full column value. Do you have a limit for string values from the DB or is the problem inside the JDBC-Driver? And, most important: Do you know a workaround or (better) a correction? Thanks in advance for an answer and best regards Wolfgang Pasche

Hi Wolfgang, There are no limitations like this in DbVisualizer and I am unable to reproduce the problem with an LVARCHAR(2048) column. I'm using Informix Dynamic Server 11.50.UC3DE IBM Informix JDBC Driver for IBM Informix Dynamic Server 4.10.JC1DE Are you using an older driver maybe? Best Regards, Hans

Hi Hans, yes, the jdbc-driver I am using is 3.70 JC4, because I connect to Informix 10. But our DBs will soon switch to Informix 11.70 or Informix 12. We already have the Informix client 4.10TC4W1, so I will try to install it and test the new jdbc driver (the new client should be able to connect to older Informix servers, otherwise I will fetch the new jdbc driver only). After testing that I will post the results here. Thank you for your recherche. Best regards Wolfgang

Hi again, I tried it now with the newest jdbc driver from IBM: Version 4.10.JC6DE. The result in the LVARCHAR column is the same as before (I will try it on an Informix server version 12, soon), but now clicking the columns tab results in the following error message: >>An error occurred while performing the operation: >>Routine (get_data_type) can not be resolved. Do you know, how to correct this? Regards Wolfgang

Hi, I experimented a bit and found out the following: - The error with the LVARCHAR column in the data display seems to be a bug in the LOAD command (the only tool we have to execute a LOAD sql command is the old SQLEditor). After loading the data with this LOAD for all values of the LVARCHAR column the LENGTH function return 2048 instead of the real lengths, When I load the data by DBVisualizer import, the values are reported with the correct lengths and then the data display works without errors. - the error from the column tab occurs only when I connect to an Informix 10 DB with the new jdbc driver. Connected to an Informix 11.70 or Informix 12 DB the column data are evaluated correctly. So the new jdbc driver seems to be incompatible to Informix 10. I now created a new driver entry in DBVis with the new jdbc driver and use the old driver for my Informix 10 DBs and the new driver for the new DBs. The LVARCHAR problem seems to be no DBVis problem, but if you would find out a workaround for this, it would be nice to post it here. Thank you for your attention and Kind regards Wolfgang

Hi Wolfgang, Thanks for posting your findings here. As you say, this seems to be a problem with the database/driver as opposed to DbVisualizer. Best Regards, Hans