Attribute data management

Transcription

1 LA561 Computer Applications in LA (GIS) Attribute data management Dr. Ragab Khalil Department of Landscape Architecture Faculty of Environmental Design King AbdulAziz University Room 103 Overview Using ArcMap tables Querying tables Table relationships Graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 2/45 Overview Using ArcMap tables Querying tables Table relationships Graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 3/45 1

2 What are attribute data? Positional data are the where things are. Attribute data are the what things are. Dr. Ragab Khalil KAAU - FED LA561: GIS 4/45 Introduction Tables are just as important as coordinate data in a GIS Tables are used to hold attribute data, and attributes control the what in a GIS Tables can be used to hold data that are not explicitly spatial in nature (related data, e.g., forest stand properties, sample data) Tables are the source of all statistics, summaries, classifications, legends, and graphs in the GIS Dr. Ragab Khalil KAAU - FED LA561: GIS 5/45 Introduction Tables are a graphical representation of tabular data Tables have their own GUI, and their own set of operations Tables in ArcMap can come from a variety of sources Multiple tables can be linked or joined based on common field values Dr. Ragab Khalil KAAU - FED LA561: GIS 6/45 2

3 Using ArcMap tables: Overview Creating tables from existing sources Creating a new table Adding fields to tables Adding records to tables Editing values in table records Calculating fields Dr. Ragab Khalil KAAU - FED LA561: GIS 7/45 Creating tables from existing sources Tables can be created from existing sources dbase files ASCII files (tab or comma delimited) INFO files ODBC connections OLE DB (Object Linking and Embedding, Database) Dr. Ragab Khalil KAAU - FED LA561: GIS 8/45 Creating tables from ODBC connections Tabular data can be obtained from ODBC databases (e.g., Oracle, Access) Dr. Ragab Khalil KAAU - FED LA561: GIS 9/45 3

4 Creating a new table New (dbase) tables can be created from scratch Creates a new file on disk New table is empty Dr. Ragab Khalil KAAU - FED LA561: GIS 10/45 Adding fields to tables Each field must be defined at add time Dr. Ragab Khalil KAAU - FED LA561: GIS 11/45 Adding records to tables Records in stand-alone tables are added New records have null values for all fields new record Dr. Ragab Khalil KAAU - FED LA561: GIS 12/45 4

5 Calculating fields Record values can be altered based on expressions Expressions can use other fields Acts on selected set of records Dr. Ragab Khalil KAAU - FED LA561: GIS 13/45 Overview Using ArcMap tables Querying tables Table relationships Graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 14/45 Querying tables: Overview Making queries Sorting records Displaying selected sets Modifying selected sets Basic descriptive statistics Table summaries Dr. Ragab Khalil KAAU - FED LA561: GIS 15/45 5

6 Making queries Selects records from tables/features from layers Dr. Ragab Khalil KAAU - FED LA561: GIS 16/45 Promoting records Displaying selected records Dr. Ragab Khalil KAAU - FED LA561: GIS 17/45 Sorting records Sorting records Dr. Ragab Khalil KAAU - FED LA561: GIS 18/45 6

7 Displaying selected sets Selected records from tables also select features from layers Dr. Ragab Khalil KAAU - FED LA561: GIS 19/45 Modifying selected sets Existing selections can be broadened or narrowed Additional query criteria Dr. Ragab Khalil KAAU - FED LA561: GIS 20/45 Basic descriptive statistics Basic descriptive statistics can be generated for a field will describe selected set (or all records if there is no active selection) Dr. Ragab Khalil KAAU - FED LA561: GIS 21/45 7

8 Table summaries Summarizing tables Creates a new table Summarizes values in numeric fields One output record per unique value in the field of interest Different summary statistics available Dr. Ragab Khalil KAAU - FED LA561: GIS 22/45 Table summaries Dr. Ragab Khalil KAAU - FED LA561: GIS 23/45 Overview Using ArcMap tables Querying tables Table relationships Graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 24/45 8

9 Table relationships: Overview Record relationships among tables Joining tables Linking tables Dr. Ragab Khalil KAAU - FED LA561: GIS 25/45 Record relationships among tables One-to-one relationship every record in Table A (Destination table) has a matching value in Table B (Source table) Table A Table B Dr. Ragab Khalil KAAU - FED LA561: GIS 26/45 Record relationships among tables Many-to-one relationship Many records in Table A have a match with only 1 record in Table B Table A Table B Dr. Ragab Khalil KAAU - FED LA561: GIS 27/45 9

10 Record relationships among tables One-to-many relationship Only 1 record in Table B has a match with many records in Table B Table A Table B Dr. Ragab Khalil KAAU - FED LA561: GIS 28/45 Joining tables Creates a virtual join (does not alter data sources) Used for: one-to-one many-to-one Dr. Ragab Khalil KAAU - FED LA561: GIS 29/45 Linking tables Does not join, but allows simultaneous selections Used for: one-to-many Dr. Ragab Khalil KAAU - FED LA561: GIS 30/45 10

11 Linking tables Does not join, but allows simultaneous selections Used for: one-to-many Dr. Ragab Khalil KAAU - FED LA561: GIS 31/45 Overview Using ArcMap tables Querying tables Table relationships Graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 32/45 Graphs from tables: Overview What are graphs? Creating graphs from tables Graph elements Graph types Graph legends Axis properties Axis increments and grid lines Displaying multiple fields Switching series and groups Dr. Ragab Khalil KAAU - FED LA561: GIS 33/45 11

12 What are graphs? Graphical representation of tabular data numbers are difficult to interpret graphs are easy to interpret Dr. Ragab Khalil KAAU - FED LA561: GIS 34/45 What are graphs? Graphs are dynamically linked to tables Dr. Ragab Khalil KAAU - FED LA561: GIS 35/45 Creating graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 36/45 12

13 Advanced properties of tables Dr. Ragab Khalil KAAU - FED LA561: GIS 37/45 Graph elements Dr. Ragab Khalil KAAU - FED LA561: GIS 38/45 Graph types A number of different types of graphs exist Dr. Ragab Khalil KAAU - FED LA561: GIS 39/45 13

14 Axis properties X and Y axes have various properties Dr. Ragab Khalil KAAU - FED LA561: GIS 40/45 Axis increments and grid lines Increments and grid lines can be formatted in different ways Dr. Ragab Khalil KAAU - FED LA561: GIS 41/45 Axis increments and grid lines Maximum value can be specified Dr. Ragab Khalil KAAU - FED LA561: GIS 42/45 14

15 Displaying multiple fields Multiple fields can be displayed in the graph Dr. Ragab Khalil KAAU - FED LA561: GIS 43/45 Summary Using ArcMap tables Querying tables Table relationships Graphs from tables Dr. Ragab Khalil KAAU - FED LA561: GIS 44/45 Next week Midterm Exam 15 points Time 60 minutes Covers all lectures Written & lab Bring a CD with you. Dr. Ragab Khalil KAAU - FED LA561: GIS 45/45 15