Attribute Data Flashcards
What are the 2 common vector file formats?
ArcGIS Geodatabase and Shapefiles.
What is an ArcGIS Geodatabase?
A silo of different point, line, and/or polygon feature classes, associated attribute data, and raster data sheets.
What is a shape file?
A loosely-proprietary ArcGIS (ESRI) data format for storing georefrencing data, geometry, and attributes.
What does the anatomy of attributes in GIS include?
Data stored in tables by fields and records, all records have the same fields, and every field has a data type.
What is a character?
Text or #’s formatted as text (strings)
What is an integer?
A # stored without decimals (shot +/- 32700, long +/- 2140000000)
What is a Floating Point?
w decimals (single precision 10^78, double precision 10^208)
What is a BLOB?
A binary large object (media attachments)
What di feature attribute tables store and access?
Spatial information (ie. feature geometry)
What kind of data do non-spatial attribute tables store?
Data with no explicit spatial component (though can be linked to spatial data through feature attribute table)
What are flat files?
All data collected in one large file.
What are the issues with flat files?
Data redundancy and data consistency.
What are keys?
Data stored in flat files that are associated by shared attributes.
What is a primary key
It is one or more attribute in a table whose value can uniquely identify a record.
What is a foreign key?
Data from a different table that can join multiple tables.
What are cardinalities?
Joined tables in relational databases that have four possible relationships (1:1, 1: many, many:1, m:m)
What is an outer join?
The default to “keep all records”
What is an inner join?
The option to “keep only matching records”
What is structured query language?
A standard database protocol adopted by most ‘relational’ databases.
What is a query?
A question posed to the database in the form of a SELECT statement.
What are the inputs that can be modified by functions?
Select (.* [records]), from (.MPs [a table]), and where (“party”)
What are spatial joins?
A way to match records from a join layer to coincident features in a target layer
What is the key characteristic of spatial joins?
No change in output layer geometry.
