Latest Contributions by MartinAmeskamp

Hi, we have a utility customer who has significantly different display performance in ArcGIS 10.2.1 (the "utility version") when displaying the same MXD on two different client machines for the same ST_GEOMETRY feature classes in the same database (Oracle 12.1). We checked the usual suspects (network latency, CPU speed etc.), but we found from Oracle traces that Oracle does significantly more work when the Mxd is displayed from client 1 than from client 2 (data is in the buffer cache for both cases, so no disk reads in either trace). We then looked at the spatial queries which look basically like this: SELECT  ... FROM MyFeatureClass WHERE SDE.ST_EnvIntersects(MyFeatuerClass.SHAPE,:1,:2,:3,:4) = 1 Bind variables :1 through :4 contain the bounding box coordinates in map units, and we found that ArcMap generates significantly different bounding boxes for the same Mxd from the two different clients. The Mxd has group layers, and the effect is different for the different group layers: Layers in one group layer show very little difference, whereas another group layer has bounding boxes that are 8 times as wide (and 8 times as high). I would have thought that ArcMap basically uses the visible map extent as a bouding box, and that is what we see on the fast client, but where does it get the large values for the slow client? I'd open a tech support case, but I have no idea how to reproduce the problem ... I have plenty of details if anyone is interested... Thanks for any ideas, Martin ... View more

Hi, we're using ArcMap 10.2.2 (on various Windows platforms) with filebased GDBs that sit on a Windows fileserver (running WS 2008 R2 or WS 2012 R2, doesn't seem to make a difference). Initially, performance is adequate, but sometimes our workflow requires that we make a copy of the file GDB while ArcMap is running, and after that, access to the database slows down dramatically. It doesn't seem to matter whether that copy is made from ArcMap or from another process, and stopping that second process doesn't improve things, either. We did some research into this phenomenon (with Sysinternals Process Monitor) and it looks to me like a second access to the various files seems to change the caching behaviour of ArcMap: File access times increase significantly, and network traffic increases. I realize this is more of a windows than an ArcGIS question, but maybe someone has come across this before, or can point me to some ressource that can explain and preferrably prevent this behaviour. Restarting ArcMap solves the problem, but given the workflow context, that's a very cumbersome workaround that makes a lot of people very unhappy... Thanks, Martin ... View more

I'm currently researching a problem (on ArcGIS Desktop 10.0 and Oracle 11.2) where we have afeature class with global IDs that shows the wrong field type (Guid rather than Global ID) in ArcCatalog and that also has lots of identical global IDs that look like this: {00000000-0000-0000-0000-000000000000}. In trying to find out if any other feature classes and tables in my database are affected (it's a big schema), I came up with the following SQL query: SELECT name,        type FROM   (SELECT name,                Extractvalue(VALUE(d), '/GPFieldInfoEx/FieldType') type,                Extractvalue(VALUE(d), '/GPFieldInfoEx/Name')      colname         FROM   sde.gdb_items_vw items,                table(Xmlsequence(Extract(Xmltype(items.definition),                '/DEFeatureClassInfo/GPFieldInfoExs/GPFieldInfoEx'))) d         WHERE  items.type = '{70737809-852C-4A03-9E22-2CECEA5B9BFA}') WHERE  colname = 'GLOBALID'        AND type <> 'esriFieldTypeGlobalID';  This returned a lot more matches than I expected, one of them being a feature class called FCL_ACCESS. I then looked up FCL_ACCESS in ArcCatalog to make sure that my SQL was OK, but ArcCatalog shows that attribute GLOBALID is of type Global ID. In order to make sure that I didn't have a mix up somewhere, I looked up the OBJECTID of the feature class description with SQL, extracted the XML definition using sdexml, fired up an XML editor and found the SQL information confirmed (attribute GLOBALID has type esriFieldTypeGuid rather than esriFieldTypeGlobalID). Also, the XML descrption showed the attribute HasGlobalID to be false. Now, I'm fairly sure that I'm not mixing up databases here, so why does ArcCatalog tell a different story from GDB_ITEMS?? Mystified, Martin ... View more

Hi, we've been using MxdPerfStat for years to analyze slow MXDs for years (mostlym on Oracle databases), and it's a great tool. There's one thing that I don't quite understand, though: Whenever MxdPerfStat finds a layer with a definition query that refers an attribute that doesn't have an index, there's a warning ("check if index exists on attribute..."). The same warning comes up when analyzing an MXD for publishing to ArcGIS Server. Why is that? In my experience, attributes used in definition queries tend to be non-selective, with a handful of different values (status, pressure level, type of building, annotation classid...) shared between many features. The database almost never uses these attributes to access the data for display in ArcMap since the spatial query is invariably more selective (unless the feature class is very small, and then indexes don't matter anyway). I've even seen plenty of cases where the presence of an attribute index makes Oracle use that index, resulting in much slower query execution. Are our databases special in the we don't need these indexes and everybody else is happy with them?? Thanks a lot, Martin ... View more