1 / 16

Introduction to ArcGIS for Environmental Scientists Module 2 – Fundamentals Chapter 7 – Queries

Introduction to ArcGIS for Environmental Scientists Module 2 – Fundamentals Chapter 7 – Queries. Chapter 7 - Objectives. Explore different ways to query databases Interactive Attribute Location (Spatial) Graphic Tips and tricks to optimize viewing geospatial data Bookmarks

quin-elliott
Download Presentation

Introduction to ArcGIS for Environmental Scientists Module 2 – Fundamentals Chapter 7 – Queries

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to ArcGIS forEnvironmental Scientists Module 2 – FundamentalsChapter 7 – Queries

  2. Chapter 7 - Objectives • Explore different ways to query databases • Interactive • Attribute • Location (Spatial) • Graphic • Tips and tricks to optimize viewing geospatial data • Bookmarks • Overview, magnify and viewer window • Options and Customizing ArcMap

  3. Why Use Selection? • Use to select other features • Export selected features to a separate file • Create a new layer • Subset faster than including entire set • Create a Report • Use selected set for further analysis

  4. Selection Layers • All vector layers are selectable by default when added to the map • Layer selectabillty is managed through the List By Selection view in the TOC Currently selected layers Number of selected features Currently selectable layers Click to change selectability Currently not selectable layers

  5. Interactive Selection Methods Create New Selection Add to Current Selection Remove from Current Selection • Shortcuts: Using Select Features tool and.. • Ctrl Key – unselects previous selected features and can select from the currently selected set • Shift Key – add features to currently selected and remove features from current selection Select from Current Selection

  6. Query – Select By Attribute • Identify Layer • Identify selection method • Last selection method used will be default • Create SQL “where” clause • Simple to complex expression • Selection can be based on one attribute or multiple • Save and reload selection expression

  7. SQL ‘Where’ Clause Tips • Strings are in single quotes • Attribute names in double quotes except for personal geodatabases – attributes are in square brackets • Wildcard Cards (all file types except personal geodatabases) • % for one or multiple characters • ‘-’ for one character • Personal Geodatabase wildcards • * for one or multiple characters • ? For one character • More Tips found in ‘Select by Attribute’ Help Button

  8. Query - Select by Location • Also known as spatial query • Selecting features based on spatial relationship to other features in different or same layer

  9. Location Selection Methods • Select by Location method options • Intersect • Within a distance • Are Within • Are Completely Within • Contain • Touch Boundary • Are Centered in • More…

  10. EPA Spatial Queries • May need a series of queries to answer GIS question • Which TRI sites that have lead emissions are within 20 miles of a school? • Which NPL sites in Illinois are within the flood extent of the 2008 Mississippi Floods? • What is the population density 10 miles from my site and what languages are spoken?

  11. Select by Graphic • Use a graphic to select features interactively 1) Draw graphic 2) Select by graphic

  12. Analytical Process • Define the problem • Define the criteria • Identify the data you need • Plan the analysis • Prepare the data for analysis • Execute the analysis • Examine and present the results

  13. Bookmarks • Save view in display area to return to it at any time • Data frame specific • Can be shared between data frames by exporting to .dat file to My Places

  14. Launch My Places from Data Frame Tools toolbar My Places • My Places dialog box lets you create and work with a list of your most frequently used or favorite addresses, locations, features, and spatial extents. • Data Frame and Map Document independent

  15. Additional Windows • Magnifier – see more detail without changing display • Move over display • – change magnification • Viewer – maintains view • Overview – full extent of data with extent box of data view • As you pan or zoom around extent box changes as well

  16. Customizing the ArcMap Window • Customize > ArcMap Options: • General Tab • Set new data visible on or off • Return to last used location when Add Data first used • Tables Tab • Change fonts, selected records color • Layout View Tab • set snap elements for guides, grid etc..

More Related