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Khóa học miễn phí SQL – Restricting and Sorting Data nhận dự án làm có lương

SQL – Restricting and Sorting Data Questions 1. Which of the following clause is used to limit the number of rows retrieved from a SELECT query? LIMIT WHERE AND FROM Answer: B. The WHERE clause is used to restrict the number of rows returned from a SELECT query. 2. Choose the database elements whose values […]

Khóa học miễn phí SQL – Manipulating Data nhận dự án làm có lương

SQL – Using Manipulating Data Oracle provide Data Manipulation Language commands to exercise data operations in the database.Data operations can be populating the database tables with the application or business data,modifying the data and removing the data from the database,whenever required. Besides the data operations,there are set of commands which are used to control these […]

Khóa học miễn phí SQL – Creating Other Schema Objects nhận dự án làm có lương

SQL – Creating Other Schema Objects Apart from tables, other essential schema objects are view, sequences,indexes and synonyms.A view is a logical or virtual table. Synonyms are simply alias names for database objects.Synonyms also simplify query writing and provide an element of system security by disguising the actual name of a database object.Sequences are special […]