DBMS вопросы и ответы для интервью
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Связанные сравнения
Вопрос 71. What are stand-alone procedures?
Procedures that are not part of a package are known as stand-alone because they independently defined. A good example of a stand-alone procedure is one written in a SQL*Forms application. These types of procedures are not available for reference from other Oracle tools. Another limitation of stand-alone procedures is that they are compiled at run time, which slows execution.
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Вопрос 72. What are cursors give different types of cursors?
PL/SQL uses cursors for all database information accesses statements. The language supports the use two types
of cursors
1.) Implicit
2.) Explicit
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Вопрос 73. What is a foreign key, and what is it used for?
A foreign key is used to establish relationships among relations in the relational model. Technically, a foreign key is a column (or columns) appearing in one relation that is (are) the primary key of another table. Although there may be exceptions, the values in the foreign key columns usually must correspond to values existing in the set of primary key values. This correspondence requirement is created in a database using a referential integrity constraint on the foreign key.
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