Data Warehousing: Pivot/Unpivot (Definitions)

"To rotate rows to columns, and columns to rows, in a cross-tabular data browser. Also refers to choosing dimensions from the set of available dimensions in a multidimensional data structure for display in the rows and columns of a cross-tabular structure." (Microsoft Corporation, "SQL Server 7.0 System Administration Training Kit", 1999)

"The process of rotating the view of data. For example, viewing what was the x-axis in the y-axis’s position and vice versa." (Microsoft Corporation, "Microsoft SQL Server 7.0 Data Warehouse Training Kit", 2000)

"The UNPIVOT operator is used within a SELECT statement to create a normalized data report from data that is stored as a spreadsheet." (Darril Gibson, "MCITP SQL Server 2005 Database Developer All-in-One Exam Guide", 2008)

"The PIVOT operator is used within a SELECT statement. It is used to create cross-tab reports (similar to a spreadsheet) from normalized data." (Darril Gibson, "MCITP SQL Server 2005 Database Developer All-in-One Exam Guide", 2008)

"The act of rotating rows to columns, and columns to rows." (Jim Joseph, "Microsoft SQL Server 2008 Reporting Services Unleashed", 2009)

[unpivot:] "To expand values from multiple columns in a single record into multiple records with the same values in a single column." (Microsoft, "SQL Server 2012 Glossary", 2012)

"To rotate a table-valued expression by turning the unique values from one column in the expression into multiple columns in the output, and perform aggregations where they are required on any remaining column values that are wanted in the final output." (Microsoft, "SQL Server 2012 Glossary", 2012)

"In the Lean start-up world, a pivot is a structured, often rapid, course correction on the basis of new market, customer, and development information." (Pamela Schure & Brian Lawley, "Product Management For Dummies", 2017)

 "1. To rotate rows to columns, and columns to rows, in a cross-tabular data browser. 2. To choose dimensions from the set of available dimensions in a multidimensional data structure for display in the rows and columns of a cross-tabular structure." (Microsoft Technet)

[unpivot:] "In Integration Services, the process of creating a more normalized dataset by expanding data columns in a single record into multiple records." (Microsoft Technet)