Re: Search fails, but only for a specific sequence

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Hallo Ginny,

neat tool, this TableDirect... how come I had never discovered it in over
three years of Mobile development? Huge speed advantage over SQL queries,
but (and it is a big 'but') there is no easy way to implement DISTINCT.
Three options are 1. a new table with only unique elements (blows the
database size), 2. filter row for row in C# (slow) or 3. use the ToTable()
function of a DataView (memory hungry). Hummm, now it looks like the SQL
query is infact the better option!

All very interesting and my original issue has solved itself anyway: a new
production with changed data (happens every 14 days) - in effect the same as
producing the index using DESC. But I think this is ignoring the real
problem - the index was faulty and this must be regarded as a bug by the
developers at Microsoft! Who know where it will appear next!

"Ginny Caughey [MVP]" wrote:

Puddles,

You wouldn't load the entire table into memory with TableDirect since you'd
specify an index name and range. But in any case since adding DESC changes
the behavior to the one you want, I'd expect there to be a value somewhere
between 'ne' and 'ney' that is causing the result you see. I think if you
look at the names in that range you'll get more insight what exactly is
happening. If you do, be sure to tell the rest of us!

--
Ginny Caughey
Device Application Development MVP

www.wasteworks.com
Software for Solid Waste Management



"Puddles" <Puddles@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:46551D72-D5A7-4039-89E8-AA78803205B1@xxxxxxxxxxxxxxxx
Hallo Ginny,

Using TableDirect would imply moving the entire table into the PDA's
memory
and paring it there with C#... then why bother with the database?

I do not think there are any strange characters causing the system to go
crazy - the looser search for 'ne%' works and includes everything that
should
be returned by 'ney%'!

I have created a workaround by adding the DESC parameter to the index
definiton (yes, the name colunm has it's own index), though I rather fear
this has simply moved the bug to a new location (I wonder which customer
will
discover it first?).

"Ginny Caughey [MVP]" wrote:

What are the medicines you would expect to find in that range of values?
I'm
guessing that accented characters specific to German might be causing the
result you're seeing.

Assuming that you have an index on Name, do you get the same result using
TableDirect access? The reason I ask is that using TableDirect no longer
uses the query processor but it does still use the index order.

--
Ginny Caughey
Device Application Development MVP

www.wasteworks.com
Software for Solid Waste Management



"Puddles" <Puddles@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:2295EF7D-6EF7-480F-A838-AFB11C0F2DFF@xxxxxxxxxxxxxxxx
This is weird! My medical database works just fine and has done since
ages,
until someone treid to look for a medicin begining with 'ney...'

Major Error 0x8007007A, Minor Error 0
SELECT * FROM t_artikel WHERE NAME LIKE 'ney%'
Der an einen Systemaufruf übergebene Datenbereich ist zu klein.

OK, so it's a German installation, but the issue is not hardware
relevant:
same on any Mobile device and on my PC. Varying the search string
usually
works, like 'ne%' is OK and 'n_y%' is ok, but 'new%' fails as does
'ney_%'.

Can anyone tell me what is going on here?

Thanks in advance.



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