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Database querying using SQL
Published in Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton, Modern Data Science with R, 2021
Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton
The GROUP BY clause allows one to aggregate multiple rows according to some criteria. The challenge when using GROUP BY is specifying how multiple rows of data should be reduced into a single value. Aggregate functions (e.g., COUNT(), SUM(), MAX(), and AVG()) are necessary.
Database querying using SQL
Published in Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton, Texts in Statistical Science, 2017
Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton
The GROUP BY clause allows one to aggregate multiple rows according to some criteria. The challenge when using GROUP BY is specifying how multiple rows of data should be reduced into a single value. Aggregate functions (e.g., count, sum, max, and avg) are necessary.
Databases
Published in Ian Foster, Rayid Ghani, Ron S. Jarmin, Frauke Kreuter, Julia Lane, Big Data and Social Science, 2020
The group by operator can be used in conjunction with the aggregate functions to group the result set by one or more columns. For example, we can use the following query to create a table with three columns: investigator name, the number of grants associated with the investigator, and the aggregate funding.
The role of education in promoting circular economy
Published in International Journal of Sustainable Engineering, 2023
Maija Tiippana-Usvasalo, Nani Pajunen, Holuszko Maria
The hypothesis was approached from two different angles in two case studies. In the first study, the method used was learning by doing. This method was employed in a project to implement CE in education in collaboration with Finnish school teachers. They were involved in the project from the start to finish, i.e. from planning the curriculum to analysing the results. In the second case study, the aim was to examine the student’s understanding of the barriers and drivers of promoting CE. There are not many studies concerning student views on this matter. The study was conducted with a select group of students in engineering. They were asked to answer three questions concerning barriers and drivers in writing. The categorisation of the collected data was based on earlier research. The materials and methods used in this article are presented below in Figure 4.
BAMN: a modeling method for business activity monitoring systems
Published in Journal of Decision Systems, 2019
Christian Janiesch, Martin Matzner
EPL uses SELECT, FROM, WHERE, GROUP BY, HAVING and ORDER BY clauses to query event streams in a similar fashion of SQL accessing tables of a database. INSERT INTO is used to specify output event streams and PATTERN as well as OUTPUT clauses to cater for other CEP specific operations. The following code segment shows the definition of an expression, which adds two basic measures and outputs all of them, which exceed the value of 500 in another event stream for further analyses. It corresponds to a composed basic measure with a minimum threshold deviation range for a target definition (cf. Figure 4).
A prototype HGIS for managing earthquake data from historical documents
Published in Geomatics, Natural Hazards and Risk, 2019
Federica Migliaccio, Mario Locati, Daniela Carrion, Livia Manenti, Marco Martoccia
Subsequently, information represented in the ERD has been translated in a logical scheme efficiently describing the information content of the conceptual model. The data types, defined for all the attributes of the entities, are either integer, varchar or double. Then, besides defining primary keys for all entities of the database, foreign keys have been introduced to implement associations between entities with one-to-many cardinality (e.g. “Place_names” contains a foreign key corresponding to the primary key of “Damaged_places”). The logical model of the proposed database, designed by SQL Power Architect Community Edition, a Free and Open Source tool by SQL Power Group Inc., is represented in Figure 2.