P

Parent:

See Parent Node .

Parent Loop:

A loop containing a single child loop (the child can contain a child loop of its own). There may be dependencies between the parent loop and child loop.

Parent Node:

A parent node is a non-atomic value, which can have one or more child nodes.

Parse:

The act of analyzing data, scanning for tokens, validating syntax, and so on.

Parser:

A program that parses as its primary function (see Parse ).

Partial Result:

A term used in this book to describe output from a query (against a database). That output includes only a portion of the results (a partial result).

Path:

A route or expression determining where something can be found within a structure of nodes (in a file system or an XML document).

Pattern Matching:

A process where an expression is matched as a pattern against elements in a text file (such as when an XML document is parsed).

Performance:

Performance is a measure of how fast database services applications, and ultimately end-users, get responses from a computer system.

Performance Tuning:

The art or act of making a computer system provide better response to end users.

PHP:

Called Hypertext Preprocessor and used to create dynamic web pages, based on flexible database content .

PL/SQL:

Oracle Database stored procedure language (Programming Language for SQL).

Platform:

A computer system, usually including both hardware and operating system.

Platform Independent:

XML is platform independent because it consists of text files, where those text files can be interpreted by any browser, on any operating system, as long as the browser software keeps pace with XML standards as released by the W3C.

Precedence:

Precedence is the order of resolution of an expression, and generally acts from left to right, across an expression.

Predicate:

In programming terms, a predicate is a single expression comparison in a WHERE clause of an SQL query command. For example, WHERE p=q contains one predicate, and WHERE p=q AND x=y contains two predicates.

Primary Key:

A primary key uniquely identifies each row in a table. The entity on the many side of the relationship has a foreign key. The foreign key column contains primary key values of the entity on the one side of the relationship.

Processing Instruction:

An XML term describing a specialized XML tag used to submit a processing request to the XML parser in a browser. In other words, a processing instruction is executed, and a non-processing instruction is not executed, but simply validated as being properly coded XML. The <xml> tag is an XML processing instruction because it determines that all text to follow should be validated as being XML data.

Program:

A piece of coding that, when executed, performs a set of steps or actions.

Programmer:

A person who writes (types) computer programs.

Programming:

The art and science of writing programs.

Programming Language:

A computer language used to write programs. C is a programming language. So is Java. A programming language is compiled (see Compiler ) and a scripting language is interpreted.

Pseudocode:

Pretend or make believe code. Used to put forward a concept or idea. The coding is not necessarily syntactically verified in any environment, SDK, programming language, database, and so on.