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Published byJulian O'Neil Modified over 11 years ago
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DB glossary (focus on typical SQL RDBMS, not XQuery or SPARQL)
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facts are rows in tables Tables have columns of some type, giving each row a number of fields (i.e. n-ary) Tables have columns of some type, giving each row a number of fields (i.e. n-ary)
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query a declarative specification of a result set of rows in terms of base tables, views, and rowset- oriented operators such as select, project, join, and union a declarative specification of a result set of rows in terms of base tables, views, and rowset- oriented operators such as select, project, join, and union uses SQL SELECT..FROM...WHERE...GROUP BY...HAVING...UNION... uses SQL SELECT..FROM...WHERE...GROUP BY...HAVING...UNION... Queries can be optimized using algebraic rewrite rules. Queries can be optimized using algebraic rewrite rules. closure - the input and output of a query is a set of rows. closure - the input and output of a query is a set of rows.
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View a named, stored, secured, and often updateable query. a named, stored, secured, and often updateable query. Some DBs support recursive views or some kind of transitive closure operator. Some DBs support recursive views or some kind of transitive closure operator.
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integrity constraints conditions about data that must hold at transaction boundaries. conditions about data that must hold at transaction boundaries. conditions are declarative and can be about data in a column, e.g. conditions are declarative and can be about data in a column, e.g. cannot be null, cannot be null, must be unique, must be unique, must be one of a defined set of values. must be one of a defined set of values. Or can relate 2 or more columns, e.g. referential integrity requires that a foreign key must refer to a primary key Or can relate 2 or more columns, e.g. referential integrity requires that a foreign key must refer to a primary key
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Triggers one of the first examples of an ECA rule one of the first examples of an ECA rule A trigger fires when a row or set of rows is inserted, deleted, or updated in a table. A trigger fires when a row or set of rows is inserted, deleted, or updated in a table. The trigger may perform arbitrary database modifications in the scope of the triggering transaction. The trigger may perform arbitrary database modifications in the scope of the triggering transaction.
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how to evolve the knowledge base: insert, update, delete insert, update, delete Transaction Transaction
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role based access control How to secure the data (facts) How to secure the data (facts)
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