MYDAC and Webservice memo problem

mapelli0 · Post by **mapelli0** » Fri 18 May 2007 14:48

Hi, I am having the strangest problem ever

I have a webservice build in DELPHI 7

on this webservice I have a connection to a Mysql DB.

I have a Myquery component with its UpdateObject set to a MysqlUpdate object and a provider with its DataSet property set to the Myquery above.

on the client side I have a ClientDataset pointed to this provider.

The problem is this:

when I edit everything on the table, the memo field included, things work great, but if I try to edit anything other them the memo, the memo gets reset. any advice?
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edited forgot to mention MyDAV version: 4.40.0.21 for Delphi 7

Antaeus · Post by **Antaeus** » Mon 21 May 2007 11:13

I do not think that usage of MyUpdateSQL component is reasonable in this case. Commands to modify data in the database should be generated by the above layer, but not by MyDAC. MyDAC just executes these commands. Try to remove the MyUpdateSQL component and test this issue again.

mapelli0 · Post by **mapelli0** » Mon 21 May 2007 12:10

If I remove the updateobject I won't be able do use like cds.edit or cds.append and all work should be done "manually" if you know what I mean.

what I did to work around the problem was, take off all memo fields from the update statement and do it from another query, witch is kind of a pain, since I have to retrieve the data, put on a memo and when I have to post/apply updates to the table I have to get the data from the memo and the generate an update statement for those fields, execute it and refresh all data. on low bandwidth places it will be very slow since the table have 135 fields and about 30 are memo.

what makes me crazy is that the only data it looses is the memo field everything else works fine, integer, strings, data, everything works fine, but the memo field gets set to null.

Antaeus · Post by **Antaeus** » Wed 23 May 2007 08:07

Unfortunately I can not reproduce the problem. Could you try to reproduce this problem in a standard applications (not a web service) and send this application to me at evgeniyd*crlab*com? This will speed up investigation of this problem. Also include the following information:
- definition of the server objects used in your example;
- instructions to reproduce the problem;
- exact version of MySQL server and MySQL client. You can see it in the Info sheet of TMyConnection Editor.

mapelli0 · Post by **mapelli0** » Wed 23 May 2007 23:20

this doesn't happen on a normal application.

maybe it has something to do with delphi provider getting lost with the memo field?

Antaeus · Post by **Antaeus** » Thu 24 May 2007 09:15

Try to minimize your applications to the maximum possible extent, so that they include only significant code. Also minimize your test data so that it includes a couple of fields and a couple of records. Send your applications to me, including definition of the server objects used in the applications. Also specify the exact version of MySQL server and MySQL client.