Arc GIS Queries Maneesh Sharma West Virginia GIS

Arc. GIS Queries Maneesh Sharma West Virginia GIS Technical Center Department of Geology and Geography West Virginia University Morgantown 26505 Maneesh. Sharma@mail. wvu. edu

Overview �Queries in feature classes ◦ Attribute Query �Demonstration ◦ Location Query �Demonstration �Query in Data driven Pages ◦ Dynamic query �Demonstration �Questions

Queries in a feature class � Attribute Query ◦ “A query that extracts data/features from a layer based on the value of its attribute data” � Query can be ◦ Simple query ◦ Compound query �Subquery

Simple Query �A query expression needs 3 components ◦ Attribute Field Operator Field Attribute Value "Assessed. Acres" >= 0. 19 ◦ The result will show a set of selected features

Simple Query � Different types of operators can be used � Calculations can be done ◦ "Assessed. Acres" >= 0. 12 * 100 Or "Perimeter" >= "Acres" * 10

Compound Query � Multiple attribute and operators can be used to create compound query ◦ Complex expressions can be created by using AND or OR "Perimeter" >= 7361. 83 or "Acres" <= 0. 35

Subqueries �A subquery is a nested query � Supported just by geodatabase data sources only � Will NOT work with shapefiles "Entity" NOT IN (SELECT "ENTITY" FROM BLDTYPES 2) � Demonstration

Location Query �A location query is based on their location relative to other features that meet certain conditions � Main ◦ ◦ ◦ types Near Intersect Inside

Location Query � Three ◦ ◦ ◦ things needed for query Layer that contains features you want to select Location relationship that needs to be analyzed Layer that contains related features “Building types within 2000 ft of selected parcel” � Demonstration �

Query in Data Driven Pages � Each layer can take advantage of the Data Driven Page setup � Layer has to have the page number from the index layer associated with the features � By setting the Page Definition by using page number, you can show or hide each feature on the map

Query in Data Driven Pages � Demonstration