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Describe and Apply Concepts Used in GIS Database Manipulation

I have installed and configured Microsoft SQL Server Enterprise within my organization to enable
versioning and multi-user editing of enterprise geodatabase datasets. Initially, this was done using
ESRI Spatial Data Engine (ArcSDE) to enable the spatial component within the relational database
system. When migrating to ArcGIS Server10.4.1 for my organization, ArcSDE command lines no
longer exist and SDE features are accomplished via ArcDesktop tools. Spatial queries are written to
views and consumed by the end user utilizing connections through ArcCatalog, allowing them access
to the features and allowing edit and post of their individual versions. An intermediate Quality Control
(QC) version is used to verify changes before posting to the Database Owner (DBO). This ensures the
organizational data standards are met and final reconcile and post makes those newly edited features
available to everyone.

Data manipulation for GIS requires a connection to some sort of data (shapefile, personal geodatabase,
file geodatabase or enterprise geodatabase). I have used Spatial and 3D Analyst to convert LiDAR
surveys (point clouds) to raster grids to facilitate the analysis of hydrologic water flows around dams.
Since this type of analysis is done over large areas, raster format is primarily the format of choice and
vector conversions are necessary. I have also used map algebra conditional statements to convert
Digital Elevation Models (DEMs) from meters to feet for analysis. I have also manipulated table data
by adding and deleting rows, calculating geometry and concatenating fields. I sometimes need to crate
joins an relationships between tabular and spatial data using unique id fields; this may entail utilizing
table commands to create the needed attributes to facility the join or relationship.
Explain How Databases Are Linked with GIS

As stated above, I started small by utilizing Microsoft Access and developing tables containing primary
and foreign key identifiers, this enabled me to take advantage of table relationships in ArcDesktop. I
would then import these files usually as a .dbf file into ArcMap for analysis.
I later learned how to create detailed schemas to implement GIS enterprise level databases for my
organization. The tables were created using Microsoft SQL Server Enterprise (MS SQL). Command
line tools were used to create the data types for the database attributes according to our spatial data
standard. Each table created requires a minimum of a unique ID field and a foreign key to facilitate
joining of additional tables within the spatial database. Once configured, I would create any additional
queries that may be needed and create views which are then indexed to store the values and make
them available to the user. I utilize ArcCatalog to create my connections to the spatial databases
that have been configured. I have setup a number of spatial database connections for internal data,
external data and raster data that our District utilizes. I also use ArcCatalog to import data from various
source types into our spatial databases for dissemination.

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