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Chapter 24: Problem 1

What are the differences between row-level and statement-level active rules?

Short Answer

Expert verified
The difference between row-level and statement-level active rules lies in when they are activated and what they act on. Row-level rules are applied to each row affected by an SQL statement while statement-level rules are triggered once per SQL statement no matter how many rows it affected.

Step by step solution

01

Define Row-Level active rules

Row-level active rules are applied to each row impacted in a table. They are triggered independently for each row that the statement affects. These types of rules are best used when dealing with business rules that focus on individual rows.
02

Define Statement-Level active rules

Statement-level active rules are only triggered once per SQL statement, regardless of the number of rows affected by that statement. This means they only activate once for each insert, update, or delete statement. They are best used when dealing with business rules that concern multi-row considerations.
03

Compare Both

Row-level rules and statement-level rules can address different types of database conditions. Whether one or the other is best to use depends on whether the conditions to be checked or actions to be performed are based on individual rows (row-level) or on the overall statement (statement-level).

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