'Foreach tuple' presentation slideshows

Evaluation of Relational Operators

490 views • 41 slides

Evaluation of Relational Operations

Evaluation of Relational Operations. Yanlei Diao UMass Amherst March 01, 2007. Slides Courtesy of R. Ramakrishnan and J. Gehrke. Relational Operations. We will consider how to implement: Selection ( ) Selects a subset of rows from relation.

447 views • 35 slides

Query Execution

Query Execution. Where are we?. File organizations: sorted, hashed, heaps. Indexes: hash index, B+-tree Indexes can be clustered or not. Data can be stored in the index or not. Hence, when we access a relation, we can either scan or go through an index: Called an access path.

337 views • 25 slides