"A method of accessing a table by reading every row in the table. Table scans are used when there are no conditions (where clauses) on a query, when no index exists on the clauses named in the query, or when the SQL Server optimizer determines that an index should not be used because it is more expensive than a table scan." (Karen Paulsell et al, "Sybase SQL Server: Performance and Tuning Guide", 1996)
"The means by which SQL Server searches a table sequentially without using an index. SQL Server starts at the beginning of the table and reads every row in the table to find the rows that meet the search criteria of the query." (Microsoft Corporation, "SQL Server 7.0 System Administration Training Kit", 1999)
"The means by which SQL Server performs a search on a table. SQL Server starts at the beginning of the table and reads every row in the table to find the rows that meet the search criteria of the query." (Microsoft Corporation, "Microsoft SQL Server 7.0 Data Warehouse Training Kit", 2000)
"A search of an entire table, row by row." (Peter Gulutzan & Trudy Pelzer, "SQL Performance Tuning", 2002)
"A data retrieval operation where the database engine must read all the pages in a table to find the rows that qualify for a query." (Anthony Sequeira & Brian Alderman, "The SQL Server 2000 Book", 2003)
"This is the process of scanning each extent of a table for a needed record." (Joseph L Jorden & Dandy Weyn, "MCTS Microsoft SQL Server 2005: Implementation and Maintenance Study Guide - Exam 70-431", 2006)
"The process of examining all rows of data in a table sequentially." (DAMA International, "The DAMA Dictionary of Data Management", 2011)
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