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Pee Dee GIS Users Group

SC GIS Professionals in the Pee Dee Area

Month

April 2010

Spacial Joins and Selections

Issue: Doing a Spacial Join or Selection returns all items.

Description:
If you join a layer to a table you may be unable to use that layer in a spacial join to another layer. When using a layer with joins in ArcMap 9.3 you might encounter the issue where all the items in a layer are selected instead of the selection based on your criteria.

Solution:
The solution is to export the layer with the join to a separate layer file, then use that layer to do the spacial join/selection.

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ESRI ArcGIS Ideas Web site

ESRI has launched the ArcGIS Ideas Web site http://ideas.arcgis.com. This site offers users a place to contribute their ideas to ESRI and have the community discuss and vote on those ideas.

The ArcGIS Ideas Web site is intended for use by ESRI customers and the GIS community at large.

Another good one is http://resources.arcgis.com/, which is really all of our support and forums wrapped up under one site with some additional information.

Ed Yankowski
ESRI-Charlotte
South Carolina Account Manager
Office: 704.541.9810 x8670
Cell: 704.241.2966
eyankowski@esri.com

SQL Challenge

SQL is the language we use to do our every day queries. SQL stands for Structured Query Language and there is an enormous amount of help to be found on the internet for this language. For most of us we use the SQL with a simple statement such as [fieldname] = “somevalue” and this is sufficient to get the job done, but SQL will do so much more.

When beginning in SQL [fieldname] = “somevalue” is an effective way to search for and find the features we are after. There are other statements that can be more generic such as [fieldname] Like “the beginningofsomevalue%” or [fieldname] Like “%theendofsomevalue” that will return the attributes that begin with some value and the % sign is a wildcard character that represents any number of characters that follow. For example if your SQL statement was [fieldname] Like “B%” then any value in the field that began with letter “B” would be selected. The % sign at the end of the some value statement requests for all characters that follow, but % sign at the beginning of the some value statement requests all characters that precede the value.

I think that most of the useful operators are on our standard “Select by Attributes” dialog box. There are some however that are not on the dialog box that are still available for use. Such as [fieldname]  IN( ‘somevalue’, ‘someothervalue’) or [fieldname]  BETWEEN somevalue AND someothervalue.

Here is a much more complicated query which finds duplicate records [fieldname] In (SELECT [fieldname] FROM [tablename] As Tmp GROUP BY [fieldname] HAVING Count(*)>1 )

So this is your mission, should you choose to accept it. In the comments area below demonstrate and explain a statement not already used. If the statement is complex submit a post where we all may learn.

South Carolina Pictometry User Group Agenda

If you aren’t on the mailing list and are planning to go to his, here’s the agenda.

  1. The date (April 15th) is a little more than 2 weeks away for the first of our annual Pictometry User Conference’s in Carolinas.  The second one will be held on May 27th in Charlotte North Carolina.  Many folks have already registered but there is still room for more people to attend.  We have lined up a very exciting program of speakers including current customers and Pictometry Technical Folks (See the newly released agenda attached).
  2. The day long event will be hosted by Palm Beach County at their Emergency Operations Center located @ 2500 City Hall Lane North Charleston, SC 29406 See map and oblique image below
  3. Remember, this is a free event (morning refreshments and lunch will be provided) and should be a fantastic opportunity for you to socialize and communicate with fellow Counties and /Cities, from across the Carolinas.
  4. To register for the event please contact Barry Grimes our Customer Relationship Representative via email at barry.grimes@pictometry.com or by phone at (585-487-1487). (We need you to register so we have a head count for lunch).  We look forward to having you there.

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