4_Lecture_Geodatabas..
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GIS Tutorial 1 Lecture 4 Geodatabases Outline Data types Geodatabases Data table joins Spatial joins Field calculator Calculate geometry ArcCatalog functions GIS TUTORIAL 1 - Basic Workbook 2 Lecture 4 DATA TYPES GIS TUTORIAL 1 - Basic Workbook 3 Directly loadable data types dBase (.dbf) Text with comma (.csv) or tab-separated values (.txt) Microsoft Access (.mdb) Microsoft Excel (.xls) GIS TUTORIAL 1 - Basic Workbook 4 Data table formats First row must have attribute names with self-documenting labels (e.g. Pop5To17, Area) Usual naming convention first character is a letter remaining characters be any letters, digits, or the underscore character All additional rows of a data table need to contain attribute values None of the rows can be sums, averages, or other statistics of raw data rows GIS TUTORIAL 1 - Basic Workbook 5 Data table formats dBase field names Maximum 10 characters GIS TUTORIAL 1 - Basic Workbook 6 Lecture 4 GEODATABASES GIS TUTORIAL 1 - Basic Workbook 7 Geodatabase types Manages features and tables inside a database management system File geodatabase stores datasets in a folder of files each dataset a file up to 1 TB in size can be used across platforms can be compressed and encrypted for read-only, secure use ESRI’s recommended choice GIS TUTORIAL 1 - Basic Workbook 8 Geodatabase types Personal geodatabase stores datasets in a Microsoft Access .mdb file storage sizes between 250 and 500 MB limited to 2GB only supported on Windows some higher level GIS functions can only be performed if a geodatabase is created ArcSDE geodatabase stores datasets in a number of optional DBMSs: IBM DB2, IBM Informix , Microsoft SQL Server , Oracle, or PostgreSQL unlimited size and users GIS TUTORIAL 1 - Basic Workbook 9 Geometric Network in a Geodatabase Example of higher level GIS Function GIS TUTORIAL 1 - Basic Workbook 10 New file geodatabase ArcCatalog: select File> New> File geodatabase or Personal geodatabase> type name of new geodatbase GIS TUTORIAL 1 - Basic Workbook 11 Import into geodatabase Shapefile features GIS TUTORIAL 1 - Basic Workbook 12 Import into geodatabase Tables GIS TUTORIAL 1 - Basic Workbook 13 Export from geodatabase GIS TUTORIAL 1 - Basic Workbook 14 Compact geodatabases File and personal geodatabases Reduces size and improves performance Compact personal geodatabases > 250 MB. Geodatabases with frequent data entry, deletion, or general editing Open geodatabases in ArcMap cannot be compacted remove any layers with a source table or feature class in that database from the TOC GIS TUTORIAL 1 - Basic Workbook 15 Compress geodatabases File geodatabases Once compressed, a feature class or table is read-only and cannot be edited Compression is ideally suited to mature datasets that do not require further editing Compressed dataset can be uncompressed to return it to its original, read-write format GIS TUTORIAL 1 - Basic Workbook 16 View geodatabases Cannot identify names in Windows Explorer Must use ArcCatalog GIS TUTORIAL 1 - Basic Workbook 17 Lecture 4 DATA TABLE JOINS & RELATES GIS TUTORIAL 1 - Basic Workbook 18 Data table joins Putting two tables together to make one table Join two tables one-to-one by row Must have the same values and data types GIS TUTORIAL 1 - Basic Workbook 19 Joins and Relates -Two methods to associate tables in ArcMap based on a common field -Join appends the attributes from one on to the other table -Relate defines a relationship between two tables GIS TUTORIAL 1 - Basic Workbook 20 Join or Relates Usage: Join- Assumes one-to-one or many-to-one cardinality - Appends the attributes of the two tables - i.e. parcel polygon table one unique permanent parcel number (ppn) is matched to an Auditor attribute characteristic table (property value) with one unique ppn Relates- Assumes many-to-many or one-to-many cardinality - Tables remain independent - i.e. if you select a building, you can find all the tenants that occupy that building. Similarly, if you select a tenant, you can find what building he/she resides in (or several buildings, in the case of a chain of stores in multiple shopping centers—a many-to-many relationship). GIS TUTORIAL 1 - Basic Workbook 21 Join example Housing heating fuel study for U.S. Counties Source: U.S. Census Data table: Census SF3 table for heating fuel by county Map Features: County polygons GIS TUTORIAL 1 - Basic Workbook 22 Data table Heating fuel table (Excel spreadsheet) GIS TUTORIAL 1 - Basic Workbook 23 Data table Heating fuel table data dictionary H040001: Occupied housing units: House heating fuel; TOTAL Units H040002: Occupied housing units: House heating fuel; Utility gas H040003: Occupied housing units: House heating fuel; Bottled; tank; or LP gas H040004: Occupied housing units: House heating fuel; Electricity H040005: Occupied housing units: House heating fuel; Fuel oil; kerosene; etc. H040006: Occupied housing units: House heating fuel; Coal or coke H040007: Occupied housing units: House heating fuel; Wood H040008: Occupied housing units: House heating fuel; Solar energy H040009: Occupied housing units: House heating fuel; Other fuel H040010: Occupied housing units: House heating fuel; No fuel used GIS TUTORIAL 1 - Basic Workbook 24 Feature class County polygons GIS TUTORIAL 1 - Basic Workbook 25 Add data and features to map GIS TUTORIAL 1 - Basic Workbook 26 Open attribute tables Find common attribute to join GIS TUTORIAL 1 - Basic Workbook 27 Data problem FIPS has leading zero and is a TEXT field. FIPS 01001 01003 01005 01007 GEO_ID2 is a NUMBER field with no leading zeros. GEO_ID2 1001 1003 1005 1007 GIS TUTORIAL 1 - Basic Workbook 28 Data solution Make a new NUMBER field in Counties attribute table and use field calculator to populate new field from old GIS TUTORIAL 1 - Basic Workbook 29 Data solution New FIPS_NUM is same as GEO_ID2 and ready to join GIS TUTORIAL 1 - Basic Workbook 30 Join tables GIS TUTORIAL 1 - Basic Workbook 31 Join result Heating fuel data is now listed for every county in the USCounties feature attribute table GIS TUTORIAL 1 - Basic Workbook 32 Permanent joins Joins are temporary and can be removed Export data to make joins permanent GIS TUTORIAL 1 - Basic Workbook 33 Choropleth map result GIS TUTORIAL 1 - Basic Workbook 34 Lecture 4 SPATIAL JOINS GIS TUTORIAL 1 - Basic Workbook 35 Spatial join example You have census block group centroids with housing fuel data You want to know housing fuel data by neighborhoods No attributes in common Spatial join needed GIS TUTORIAL 1 - Basic Workbook 36 Spatial joins Points to polygons Spatially joins points (block centroids) within polygons (neighborhoods) Joins using “shape” (not attribute field) GIS TUTORIAL 1 - Basic Workbook 37 Spatial joins Right click polygon layer (neighborhoods) GIS TUTORIAL 1 - Basic Workbook 38 Join result New polygon feature GIS TUTORIAL 1 - Basic Workbook 39 Join result Counts and sums GIS TUTORIAL 1 - Basic Workbook 40 Count result Number of points in each polygon GIS TUTORIAL 1 - Basic Workbook 41 Sum result Every block group centroid has associated data (e.g. H040004, heating electricity shown in labels) GIS TUTORIAL 1 - Basic Workbook 42 Sum result One neighborhood example Central business district 4 block groups Housing units with electricity fuel (80 + 299 + 128 + 292 ) Sum = 799 GIS TUTORIAL 1 - Basic Workbook 43 Choropleth map result (sum) GIS TUTORIAL 1 - Basic Workbook 44 Choropleth map result (sum) GIS TUTORIAL 1 - Basic Workbook 45 Other spatial joins Polygons to points Example: ATM robberies (points) need neighborhood name GIS TUTORIAL 1 - Basic Workbook 46 Polygon to point join result Neighborhood name shows on each point GIS TUTORIAL 1 - Basic Workbook 47 Other spatial joins Points to points Example: What is the distance of a burglary to the nearest commercial property? GIS TUTORIAL 1 - Basic Workbook 48 Point to point join result Distance to nearest commercial property shows on each burglary point GIS TUTORIAL 1 - Basic Workbook 49 Lecture 4 FIELD CALCULATOR GIS TUTORIAL 1 - Basic Workbook 50 Sample functions Performs numeric calculations Populates field Concatenates text data GIS TUTORIAL 1 - Basic Workbook 51 Field calculator functions Calculate acres to square miles GIS TUTORIAL 1 - Basic Workbook 52 Field calculator functions Populate field with county name GIS TUTORIAL 1 - Basic Workbook 53 Field calculator functions Concatenate house number and street fields GIS TUTORIAL 1 - Basic Workbook 54 Lecture 4 CALCULATE GEOMETRY GIS TUTORIAL 1 - Basic Workbook 55 Polygon/point centroids Advanced calculations for finding a polygon’s point centroid GIS TUTORIAL 1 - Basic Workbook 56 Calculate XY fields Add new X and Y fields in the attribute table GIS TUTORIAL 1 - Basic Workbook 57 Calculate XY fields Calculate geometry for X field, repeat for Y GIS TUTORIAL 1 - Basic Workbook 58 XY field results Results are X and Y values based on map properties (e.g. Long/Lat or XY feet) GIS TUTORIAL 1 - Basic Workbook 59 Export XY coordinates GIS TUTORIAL 1 - Basic Workbook 60 Add XY data table GIS TUTORIAL 1 - Basic Workbook 61 Export as shapefile XY events should be exported as permanent shapefile or feature class GIS TUTORIAL 1 - Basic Workbook 62 Calculate area Add area field and calculate geometry GIS TUTORIAL 1 - Basic Workbook 63 Calculate perimeter Add perimeter field and calculate script GIS TUTORIAL 1 - Basic Workbook 64 Calculate length Add length field and calculate script GIS TUTORIAL 1 - Basic Workbook 65 Lecture 4 ARCCATALOG FUNCTIONS GIS TUTORIAL 1 - Basic Workbook 66 Basic functions Copy, paste, rename, etc. GIS TUTORIAL 1 - Basic Workbook 67 View and edit properties Projections, fields, etc. GIS TUTORIAL 1 - Basic Workbook 68 View metadata GIS TUTORIAL 1 - Basic Workbook 69 Edit metadata GIS TUTORIAL 1 - Basic Workbook 70 Create new files Geodatabases, tables, features, etc. GIS TUTORIAL 1 - Basic Workbook 71 Summary Data types Geodatabases Data table joins Spatial joins Field calculator Calculate geometry ArcCatalog functions GIS TUTORIAL 1 - Basic Workbook 72
