Query is not understandable - using field Fulltext search [Tags] = “foo”

Question

I have a problem that only happens rarely with FT search. but once it happens it stays. I use the following search term in the FT search box in Lotus Notes

[Tags] = "foo"

in most application this search term work fine. but for some applications this search term gives the error "query is not understandable".

It does not matter if I replace the value, e.g [Tags] = "boo" produce the same result. and also FIELD Tags = "boo". for the record [Tag] = "foo" works fine so it seem be issues with the field or field name.

• The problem only happens in some applications. Once this problem start happening no views can be searched using that search query and I get the error message everytime I search.
• It does not help to remove, compact and re-create the FT index.
• I get the same error in xpages when using the same search query in a view data source.
• I have seen this problem using other fieldnames as well in other application.
• If I remove the FT index the search query works
• Creating a new copy of the "broken" database does not resolve the problem
• I tried to have only one document in database, create a new FT index. the document in view does not have the field "Tags" still not working. (there are other forms in db with the fieldname "Tags")

This is a real show stopper for me as I have built some of my XPages based on search values from specific fields

• In my own invstigation of this problem I think it has to do with some sort of bug in the FT index. There seem to be some data contained in documents or forms that causes the FT index to not work correctly.

I am looking for a solution to this problem as I have not found a way to repair it once it has become broken.

Update:

It does not help to follow this procedure https://www-304.ibm.com/support/docview.wss?uid=swg21261002

Here is my debug info

[1078:0002-2250] IN FTGSearch

[1078:0002-2250] option = 0x400219

[1078:0002-2250] Query: ( FIELD Tags = "foo")

[1078:0002-2250] OUT FTGSearch error = F09

[1078:0002-2250] FTGSearch: found=0, returned=0, start=0, count=0, limit=0

Answer 1

It sounds like you need to fix the UNK table with a compact. Here is the listing of compact options, use a copy style not in place.

http://www-01.ibm.com/support/docview.wss?uid=swg21084388

Answer 2

If Tags field is sometimes numeric, I would advise looking at the database design. The UNK table is a table of all fields in the NSF. The first time a field name is used, it is stored in the UNK table as that data type. Full text searching uses that data type and only that data type. If you have a field Tags on more than one form in a database, once numeric and once text, you're in for big trouble with full text searches. The datatype in searches will depend on which datatype the field was on the first document saved which had that field. Even if you delete all documents that have it as numeric, you won't change the UNK table without the compact. Sounds like that's what you have here. Ensure the database never stores Tags as numeric. Delete or change all docs with it stored numeric. Then compact.

Answer 3

Thank you all for answering. I learned a whole lot about UNK tables and FT index today.

The problem was that I had a numeric field called "Tags" in a form that I hadn't looked at and really didn't think that it would contain a field by that name.

after using the DDE search I found all instances of the tags field and could eaily locate the problem form. I renamed the field in the form, removed the FT indx , used compact -c and recreated the ft index. now everythig is working fine.

One other thing to notice is that I have several databases with the same design but only a few of them had the ft index problem, the reason for this is probably because some of these databases was created after the form with the faulty Tags field was created.

I am so happy to have solved this.

lessons learned If you plan to use fulltext index in your application. make sure you do not have the same field name in different forms and use different field types.

from now on I will probably use shared fields more :-)

One more thing we discovered You actually do not need notes peek to find out which field tpe is stored in the UNK table. you can use the "Fields" button in the searchbar. if you select the field and the right hand box displays "contains" you know the unk table has a text field type set.