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Data Definition Language (SQL DDL)

The Data Definition Language is intended for creating, modifying and deleting database objects. Major objects of a relational database are tables. Let’s start with them.

There are two types of tables – permanent (base) and temporary ones. Temporary tables exist only for the duration of the user session they have been created in. If these tables aren’t deleted explicitly during the session, they will be automatically removed from memory when it ends. Base tables are intended for long-term information storage in the database.

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aggregate functions Airport ALL AND AS keyword ASCII AVG Battles Bezhaev Bismarck C.J.Date calculated columns Cartesian product CASE cast CHAR CHARINDEX Chebykin check constraint classes COALESCE common table expressions comparison predicates Computer firm CONSTRAINT CONVERT correlated subqueries COUNT CROSS APPLY CTE data type conversion data types database schema DATEADD DATEDIFF DATENAME DATEPART DATETIME date_time functions DDL DEFAULT DEFAULT VALUES DELETE DISTINCT DML duplicates edge equi-join EXCEPT exercise (-2) More tags
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