|Statewide Parcel Participator:||yes|
|Assessor Office URL:||http://www.columbiaco.com/index.aspx?nid=15|
GIS Dept URL:
|Last Updated:||2013-04-11 10:33:09|
Primary Assessment Contact
|Organization:||Columbia County Assessor's Office|
|Address:||341 East Main St.|
|City, St, Zip:||Dayton, WA 99328-1361|
|Contact Last Updated:||2012-08-09 10:52:44|
Primary GIS Contact
|City, St, Zip:||,|
|Contact Last Updated:||2007-09-20 17:02:48|
The normalized Statewide Parcel Database consists of multiple related tables, relationship classes and lookup tables. Detailed information about the database schema can be found on the technical documentation page.
QA/QC Process Description
- While processing and normalizing the data for each county to a standardized statewide dataset, five possible procedures could have been applied: Removing Duplicate Parcels, Flattening Stacked Parcels, Creating Multipart Parcels, Removing Duplicate Names, and Removing Duplicate Taxrolls.
- The data for each county was tested to see whether or not these five procedures were applied. For each of these procedures applied in a county, one test parcel to which a process was applied was selected and tested to ensure the procedure was applied correctly.
- A parcel to which none of the procedures was applied was also tested to make sure all of the normalized attributes in the original data were correctly transferred to the final dataset.
- It is therefore possible that up to six data quality tests were performed for each county.
QA/QC Procedure DescriptionsThe following five Procedures were performed in this order on the data for each county.
- Removing Duplicate Parcels (PARCELS:DUPLICATE): There are two or more polygons representing a single parcel in the original data. They have the same geometry and identical attribute information. These are assumed to be multiple copies of the same parcel, and so duplicates are removed leaving a single polygon, and single set of attribute information in the final database. This flag tells how many duplicates of the parcel were in the original data.
- Flattening Stacked Parcels (PARCELS:FLATTENED): There are two or more polygons representing a parcel in the original data, however, while sharing the same geometry, they have different attributes. These are assumed to be multiple owners for the same parcel. The polygon only needs to be in the final database a single time, but all original attribute information for the different owners needs to be retained. This flag tells how many stacked polygons there were in the original data for each parcel.
- Creating Multipart Parcels (PARCELS:AGGREGATED): There are two or more polygons in the original data with different geometries but, identical attribute information. It is assumed that these parcels are all owned by the same owner. The original polygons are all retained as a single, multipart polygon, but duplicate versions of the attributes are removed. Only a single copy of the attribute information is needed in the final database. This flag tells how many parcels were aggregated into each multipart polygon.
- Removing Duplicate Taxrolls (TAXROLL:FLATTENED): Two or more parcels in a county have identical taxroll attributes. These attributes only need to be in the final database a single time. This flag records how many of the original parcels shared each set of taxroll attributes.
- Removing Duplicate Names (NAMES:FLATTENED): Two or more parcels in a county have the same name attributes in the original data. These attributes only need to be in the final database a single time. This flag records how many of the original parcels shared each set of name attributes.