Quiz 1 Set A

This statement is true because triggers in programming typically consist of three components: the event, which is the specific action or occurrence that initiates the trigger; the condition, which is a set of criteria that must be met for the trigger to activate; and the action, which is the specific task or set of tasks that the trigger performs when it is activated. These three parts work together to create a trigger that responds to specific events and conditions in a program.

This statement is true because in most programming languages, a procedure or function is executed by calling it by its name. The name of the procedure is used as a reference to locate and execute the code within the procedure. By calling the procedure, the program transfers control to the code inside the procedure and executes it.

SQL-invoked routines can be both procedures and functions. Procedures are a set of SQL statements that perform a specific task and can be called multiple times. Functions, on the other hand, return a single value and can be used in SQL statements. Therefore, both procedures and functions are examples of SQL-invoked routines, making option C the correct answer.

Views in a database are created by executing a CREATE VIEW SQL command. This command allows users to create a virtual table that is based on the result of a query. The view can then be used to retrieve data from multiple tables or to simplify complex queries. By creating views, users can easily access and manipulate data without needing to write complex queries each time. Therefore, the statement that views are created by executing a CREATE VIEW SQL command is true.

The correct answer is B.

A stored procedure is compiled and its query plan is cached. A is incorrect because stored procedures are faster. C is incorrect because Transact-SQL statements do not have to be shorter in stored procedures. D is incorrect because the same number of commands are available to both.

Constraints are a special case of triggers because both are used to enforce rules and conditions on the data in a database. However, triggers are specific actions that are automatically executed when a certain event occurs, while constraints are rules that are applied to the data to ensure its integrity and consistency. Therefore, it can be said that constraints are a subset or a special case of triggers, as they are a type of rule that can be enforced through triggers.

A procedure is a set of instructions or a sequence of actions that can be stored within a database. It is given a unique name to identify it and can be called or executed by using that name. Therefore, all of the given options are correct as a procedure is stored within the database, given a unique name, and called by name.

Triggers are a named set of SQL statements that are executed automatically when a specific event, such as a data modification, occurs in the database. They are used to enforce business rules, maintain data integrity, and automate certain actions. Stored procedures, on the other hand, are named sets of SQL statements that are stored in the database and can be executed on demand. Treatments and trapdoors are not relevant terms in the context of SQL.

A is correct.

The data resides in the Inserted and the Category tables. B is incorrect because the data also resides in the Category table. C is incorrect because the data also resides in the Inserted table. D is incorrect because only UPDATE triggers affect both the Inserted and Deleted tables.

In many programming languages and systems, including databases and event-driven systems, the "@" symbol is commonly used to declare variables in triggers. This symbol is used to differentiate variables from other elements in the code and to indicate that a specific value will be assigned to the variable. Therefore, the correct answer is b) @.

Routines are a set of instructions or procedures that need to be explicitly called in order to run. Unlike triggers, which are automatically executed in response to a specific event, routines require manual invocation. Therefore, routines are the correct answer to the question.

SQL-invoked routines, such as stored procedures or functions, provide several advantages. They enhance efficiency by reducing network traffic and improving performance. They promote sharability by allowing multiple users to access and execute the same routine. They also enhance security by allowing the database administrator to control access and permissions. However, flexibility is not an advantage of SQL-invoked routines as they are predefined and cannot be easily modified or adapted to changing requirements.

Triggers in coding are used to automatically perform certain actions when a specific event occurs. The coding structure for triggers typically includes four components: event, condition, action, and selection. The event specifies the trigger point or the event that triggers the action. The condition specifies the criteria that must be met for the trigger to activate. The action specifies the specific task or action that is performed when the trigger is activated. However, selection is not a part of the coding structure for triggers, so the correct answer is C) selection.

A function can have both input parameters and return a single value or no value at all. However, it cannot directly return multiple values. To return multiple values, we can use data structures like arrays or objects, or we can use output parameters to modify the values of variables passed as arguments to the function. Therefore, the statement that a function can return multiple values is false.

The correct answer is B.

He needs to delete the data from the Sales table if the rule fails. A is incorrect because the Inserted table can never have any action performed on it other than a SELECT statement. C is incorrect because the trigger cannot know what to do if John doesn’t code for it. D is incorrect because, again, the Inserted table can only have data selected from it.

Triggers can indeed be used to ensure referential integrity, enforce business rules, create audit trails, and replicate tables. However, triggers can also call other triggers. Therefore, the given statement that triggers cannot call other triggers is incorrect.