Working with ArcGIS Data
Data Management and Tips
Your friend…..ArcCatalog
File Types
• Shapefiles
– Contain one feature
class
– Points, lines, or
polygons
• Coverages
– Contain multiple
feature classes
• Multiple files on disk
for each coverage file
• May cover multiple
folders as well
File Types
• Geodatabase
• Contain multiple feature
classes including tables
not linked to spatial data
• Can store topological
relationships between
features and feature
classes
• Also store rules and
dictate how features
behave
• Personal Geodatabases
• Enterprise Geodatabase
File Types
• Layer file
• Raster
• Grids
• Tables
• CAD Drawings
File Types
The map document
•Stores collections of data for
repeated viewing and analysis
•Contains one or more data frames
•Stores current properties for each
layer (symbols, etc)
•Stores a page layout for printing
•Stores references to files--not the
actual data
Copyright © 2006 by Maribeth H.
Price
C:\mgisdata\usa\states.shp
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Map docs and data files
Files on disk
Points to
data
Copyright © 2006 by Maribeth H.
Price
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• Same data can be used
by many map documents
• Edits made in one
document appear in ALL
• Shipping map document
without its data is
useless
• Changing locations of
document or data can
cause problems
Causes of broken data links
Broken data links occur when a map document cannot find data using the
stored pathname
C:\mgisdata\usa\supersites.shp ??
• Some causes
– Data were moved or
deleted
– Drive not available
– Map document copied to
different computer
– Data not sent with map
D:\mgisdata\usa\supersites
Copyright © 2006 by Maribeth H.
Price
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Pathnames
Absolute paths always start at
the top of the data tree
C:\
C:\mgisdata\usa\states.shp
mgisdata
Relative paths start at the
location of the map document
Usa
--States
--Cities
--Counties
MapDocuments
..\usa\states.shp
--ex_1.mxd
--ex_2.mxd
--ex_3.mxd
Broken data links occur
when a map document
cannot find data using the
stored pathname
?
Copyright © 2006 by Maribeth H.
Price
.. Means go up
one level
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When to use…
• Absolute paths
• Relative paths
– Data placed on
central server for
access by many
– Data will never be
moved or rearranged
– You want to be able
to transfer map docs
without transferring
data also
Copyright © 2006 by Maribeth H.
Price
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– When you plan to
keep data with its
map documents and
move them together
as a set
– When you want to
distribute maps/data
to other
organizations
Connecting to folders
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Copyright © 2006 by Maribeth H. Price
ArcCatalog
• Should always be used to delete, copy,
rename and modify GIS data
• Allows users many different ways to
view data
– Contents
– Preview
– Description
Contents
Metadata
Preview
Description
• Contains
important
information about
data
– Who created it,
where it came
from, coordinate
system, etc.
• Metadata has
hundreds of pieces
of information
– Much of the
metadata is
entered by ArcGIS
itself.
ArcCatalog
ArcCatalog
Windows
Explorer
AVOID SPACES IN FOLDERS and
FILENAMES
Spaces are Evil
Copyright © 2006 by Maribeth H.
Price
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