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  2. Database trigger - Wikipedia

    en.wikipedia.org/wiki/Database_trigger

    IBM DB2 for distributed systems known as DB2 for LUW (LUW means Linux, Unix, Windows) supports three trigger types: Before trigger, After trigger and Instead of trigger. Both statement level and row level triggers are supported. If there are more triggers for same operation on table then firing order is determined by trigger creation data.

  3. Data definition language - Wikipedia

    en.wikipedia.org/wiki/Data_definition_language

    In the context of SQL, data definition or data description language (DDL) is a syntax for creating and modifying database objects such as tables, indices, and users. DDL statements are similar to a computer programming language for defining data structures, especially database schemas. Common examples of DDL statements include CREATE, ALTER ...

  4. Data control language - Wikipedia

    en.wikipedia.org/wiki/Data_Control_Language

    In the second example, REVOKE removes User1's privileges to use the INSERT command on the table Employees. DENY is a specific command. We can conclude that every user has a list of privilege which is denied or granted so command DENY is there to explicitly ban you some privileges on the database objects.:

  5. SQL syntax - Wikipedia

    en.wikipedia.org/wiki/SQL_syntax

    A derived table is the use of referencing an SQL subquery in a FROM clause. Essentially, the derived table is a subquery that can be selected from or joined to. The derived table functionality allows the user to reference the subquery as a table. The derived table is sometimes referred to as an inline view or a subselect.

  6. Hierarchical database model - Wikipedia

    en.wikipedia.org/wiki/Hierarchical_database_model

    The organization provides each employee with computer hardware as needed, but computer equipment may only be used by the employee to which it is assigned. The organization could store the computer hardware information in a separate table that includes each part's serial number, type, and the employee that uses it. The tables might look like this:

  7. Unique key - Wikipedia

    en.wikipedia.org/wiki/Unique_key

    When the data model is instantiated into a physical database, it is the key that the system uses the most when accessing the table, or joining the tables together when selecting data. Alternate A non-primary key that can be used to identify only one row in a table. Alternate keys may be used like a primary key in a single-table select. Foreign

  8. User provisioning software - Wikipedia

    en.wikipedia.org/wiki/User_provisioning_software

    A user provisioning system may implement one or more processes to achieve the aforementioned goals. These processes may include: Auto-provisioning. For example: Monitor an HR application and automatically create new users on other systems and applications when new employee records appear in the HR database. Auto-deactivation. For example:

  9. Database engine - Wikipedia

    en.wikipedia.org/wiki/Database_engine

    A database engine (or storage engine) is the underlying software component that a database management system (DBMS) uses to create, read, update and delete (CRUD) data from a database. Most database management systems include their own application programming interface (API) that allows the user to interact with their underlying engine without ...