database diagrammer bug??

This morning I spent 3 hours drawing a diagram for 75 tables, had it looking
very nice, was saving on a regular basis, but then I couldn't save data
structure changes to a table until I closed the diagram out, which also
wanted to save one last time. So when I opened it back up, nearly all of my
work was gone. Tables that I had removed are now back. Objects are not
arranged like I had them, they're all in a straight line. All relationships
except for 4 or 5 are gone. I pretty much wasted all that time. Is this a
bug?
I am having other Enterprise Manager problems too, like I cannot see bit
fields in my available fields list while creating indexes. I would think
that I should reinstall Enterprise Manager but I've reinstalled twice with
the client tools on sql2k and still have the bit field problem.
thank you,
CoryI have not used diagraming in sql server enterprise manager as extensively a
s
you have. In general it is not a good tool for creating the database diagram
.
It is good for a few tables.
You should consider using a tool that was properly built for diagraming.
Like ErWin, I even Use Visio Professional Edition.
It is possibly a bug, but I would definatelly advise closing the diagram
prior to making table changes.
As far as bit fields not showing up when creating indexes.
This is not a bug. you cannot create an index on a bit.
Indexes are only valuable when there is a varied amount of data. For a bit
there are only 2 possible values 0 and 1, so in the best case scenario the
chance of a record being selected is 50%. The selectivity of the data of a
column with a bit data type is not great enough to justify the cost of havin
g
to look at the index.
"Cory Harrison" wrote:

> This morning I spent 3 hours drawing a diagram for 75 tables, had it looki
ng
> very nice, was saving on a regular basis, but then I couldn't save data
> structure changes to a table until I closed the diagram out, which also
> wanted to save one last time. So when I opened it back up, nearly all of
my
> work was gone. Tables that I had removed are now back. Objects are not
> arranged like I had them, they're all in a straight line. All relationshi
ps
> except for 4 or 5 are gone. I pretty much wasted all that time. Is this
a
> bug?
> I am having other Enterprise Manager problems too, like I cannot see bit
> fields in my available fields list while creating indexes. I would think
> that I should reinstall Enterprise Manager but I've reinstalled twice with
> the client tools on sql2k and still have the bit field problem.
>
> thank you,
> Cory
>
>|||Thanks for the advice regarding the software tools.
As for the indexes, yes, you can have bits in indexes but only with sql2k.
I understand the reasoning behind not indexing a column based on a bit, but
it would speed things up in a covering situation if you could put your more
selective fields first then put the bit field last because sql server would
not have to do a bookmark lookup, which is all I want it for. I have some
situations where multiple fields are used in a query but a bookmark lookup
is needed because of that one stupid bit field. I can write scripts that
add bits to indexes, I just cannot do it in Enterprise Manager. I have
confirmed this with Kimberly Tripp, and if she says it must be a bug, I
doubt many of us should argue, I just don't know what to do about it. I was
ok with just writing scripts as a workaround until I lost 3 hours worth of
work earlier and thought that it may be related.
thanks,
Cory
"rmartinez" <rmartinez@.discussions.microsoft.com> wrote in message
news:8E0B6BE8-CCB0-478D-A0C1-9256B8753281@.microsoft.com...
>I have not used diagraming in sql server enterprise manager as extensively
>as
> you have. In general it is not a good tool for creating the database
> diagram.
> It is good for a few tables.
> You should consider using a tool that was properly built for diagraming.
> Like ErWin, I even Use Visio Professional Edition.
> It is possibly a bug, but I would definatelly advise closing the diagram
> prior to making table changes.
> As far as bit fields not showing up when creating indexes.
> This is not a bug. you cannot create an index on a bit.
> Indexes are only valuable when there is a varied amount of data. For a bit
> there are only 2 possible values 0 and 1, so in the best case scenario the
> chance of a record being selected is 50%. The selectivity of the data of a
> column with a bit data type is not great enough to justify the cost of
> having
> to look at the index.
> "Cory Harrison" wrote:
>