Refresher/SQL/Basic Concepts

Presentation
Constraint: an input filter Denormalizing: performance improvement through reduction in number of joins needed for data processing Group by and order by clauses: expensive due to creation of temporary tables Indexes' tradeoffs: faster retrieval, slower updates Join: a logical connection between two tables Normalizing: eliminating redundant information and making it easier for future updates Primary key: a combination of columns which uniquely specify a row Trigger: the code automatically executed in response to certain table events Where vs having: where is a restriction and having is a filter Wildcard: % using LIKE

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