Programming PL-SQL Glossary

PL/SQL stands for Procedural Language extension of SQL. PL/SQL is a combination of SQL along with the procedural features of programming languages. It was developed by Oracle Corporation in the early nineties to enhance the capabilities of SQL. The PL/SQL Engine: Oracle uses a PL/SQL engine to processes the PL/SQL statements. A PL/SQL code can be stored in the client system (client-side) or in the database (server-side).

Datatype

Defines the type of information that can be stored, such as dates, numbers, or characters.

Exception

An error condition that changes the normal flow of control within a program.

Field

An area of a database record, or graphical user interface form, into which a particular item of data is entered.

Global

Globals do not respect the boundaries of program interfaces. You can read and write globals without using the parameter list of a module.

Identifier

An identifier is a name for a PL/SQL object such as constant, variable, exception, package, procedure, function.

Legacy system

An existing information system using old technology.

Literal

A constant made available to a process, by inclusion within the executable text.

Loop

A sequence of instructions that the processor repeats, either until some condition is met, or indefinitely.

Operator

A symbol used as a function, with infix syntax if it has two arguments (e.g. "+") or prefix syntax if it has only one (e.g. Boolean NOT).

Oracle's Program Global Area (PGA)

The PGA is a memory buffer that contains data, process information, session information, and cursors for a server process.

Package

A database program consisting of one or more procedures. A package executes when called using SQL or a programming language interface.

PL/SQL

Oracle's Procedural Language extensions to SQL. A proprietary programming language for Oracle databases.

Pragma

A pragma is a special instruction to the compiler. Also called a pseudoinstruction, the pragma does not change the meaning of a program. It simply passes information to the compiler.

Procedure

A database program that contains PL/SQL commands. A procedure can be contained within a package or can be stand alone. A procedure executes when called using SQL or a programming language interface.

Record

An ordered set of fields.

Reserved word

A word which has a pre-defined meaning and thus has restricted use.

Runtime

The time when a program is actually executed.

SQL

Structured Query Language.

Subblock

A block within a block.

Truth table

A table listing all possible combinations of inputs and the corresponding output of a Boolean function such as AND, OR, NOT, IMPLIES, XOR, NAND, NOR. Truth tables can be used as a means of representing a function.

Unary

A description of an operator which takes one argument, e.g. the unary minus operator which negates its argument.

View

A presentation of the data in one or more tables. A view is the result of a SQL query.

Virtual table

A table that does not physically exist but emulates the functionality of a traditional database table.

Work area

An area of work internally assigned by the system for temporary operations and calculations, such as cursor processing, sorting, and more.