Database and SQL

Implicit cursors are used by Oracle for each UPDATE, DELETE and INSERT SQL commands.

PL/SQL is an extension of SQL that allows for procedural logic. It supports DML (Data Manipulation Language) commands like SELECT, INSERT, UPDATE, and DELETE.

In Oracle SQL, REF is a built-in operator that returns a reference to an object in an object table.

PL/SQL is a procedural extension of SQL. It supports all SQL statements, including DML and DCL, by embedding them directly into its procedural blocks.

A PL/SQL block is divided into three sections: the declarative part (for variables/constants), the executable part, and the exception handling part.

CAST is a standard SQL function used to convert a value from one data type to another, which is used within SQL statements.

The EXIT WHEN statement is used in PL/SQL loops to terminate the loop execution immediately when a specific condition is met.

The GOTO statement allows the program to jump unconditionally to a specified label within the same block.

PL/SQL data types are generally classified into two categories: scalar data types and composite (or complex) data types.

In PL/SQL, an exception is an error condition that occurs during the execution of a program, which interrupts the normal flow.

All variables, constants, and user-defined exceptions must be declared in the declarative section of the PL/SQL block.

Exceptions in PL/SQL are classified into two types: predefined (system) exceptions and user-defined exceptions.

This property of a transaction states that the changes applied to the database by a committed transaction must persist in the database.

This property of transaction refers to multiple transactions, accessing the same database at the same time.

This component in the active database rules is the one that determines whether the rule action should be executed or not.