Server-Side Programming, PHP, and Database Connectivity

Comprehensive vocabulary flashcards covering server-side scripting concepts, PHP syntax, array and file handling, sessions, cookies, and MySQL database connectivity with MySQLi.

Server-Side Scripting

The process of executing scripts on a web server to generate dynamic web pages or web applications and perform server-related tasks.

PHP

An open-source, server-side scripting language originally meaning 'Personal Home Pages' and later recursively 'PHP: Hypertext Preprocessor', created by Rasmus Lerdorf in 1994 to create dynamic web pages.

Pure PHP Files

Files that contain only PHP code without HTML tags, commonly used for server-side processing, background tasks, or data manipulation.

XAMPP

A local PHP development environment package that includes the Apache web server, PHP, and MySQL database server.

Constant (PHP)

An identifier for a fixed value that cannot be changed or redefined during script execution, defined using the define() function and accessed without a dollar sign ($$).

Resource (Data Type)

A special PHP data type that stores a reference to external resources and functions, such as an open file handle.

NULL (Data Type)

A PHP data type that represents a variable that has no value assigned to it.

strlen()

A built-in PHP string function that calculates and returns the number of characters in a given string.

explode()

A built-in PHP function that splits a string into an array based on a specified delimiter.

trim()

A PHP string function that strips whitespace and predefined characters from both the beginning and the end of a string.

Indexed Array

An array type that stores elements identified by numeric keys starting from index $0$ and increasing incrementally.

Associative Array

An array type that stores data using named key-value pairs, where the keys are strings.

Multidimensional Array

An array that contains one or more nested arrays within its elements.

break Statement

A jump statement that immediately terminates the execution of the current loop or switch block and transfers control to the statement following it.

continue Statement

A jump statement that skips the remaining code in the current iteration of a loop and moves directly to the next iteration.

var_dump()

A PHP function that displays structured information about an expression or variable, including its data type, value, and length.

$_GET

A PHP superglobal array used to collect form data submitted via an HTTP GET request, where parameters are appended directly to the URL.

$_POST

A PHP superglobal array used to collect form data sent through an HTTP POST request, where parameters are passed inside the request body rather than the URL.

Session

A server-side mechanism used to preserve user state and store data across multiple requests during a website visit, identified via a unique session ID.

PHPSESSID

The default cookie name used by PHP to store and transfer the unique session ID on the client's browser.

session_start()

A PHP function that initializes a new session or resumes an existing session; it must be called before sending any HTML output.

session_destroy()

A PHP function that completely destroys all data registered to the active session on the server, commonly used during logout.

Cookie

A small text file generated by the server and saved on the client's web browser to recognize users, maintain state, track activity, and retain preferences.

setcookie()

The PHP function used to create, transmit, update, or delete an HTTP cookie on the client's browser.

file_exists()

A PHP file-handling function that verifies whether a file or directory exists on the server's file system, returning TRUE or FALSE.

fopen()

A PHP function that binds a named resource to a stream using a specified mode (such as 'r', 'w', or 'a') for reading or writing.

file_put_contents()

A PHP function that writes data directly to a file in a single step, handling opening, writing, and closing the file internally.

feof()

A PHP function that tests whether the file pointer has reached the end-of-file mark on an open file handle.

copy()

A PHP function that duplicates a file from a specified source location to a destination path, returning TRUE on success.

rename()

A PHP function used to rename a file or move it from one directory to another on the server.

unlink()

A PHP function that permanently deletes a specified file from the server's file system.

MySQL

An open-source Relational Database Management System (RDBMS) that organizes and manages data in structured tables using Structured Query Language (SQL).

ACID Properties

A set of four database transaction principles: Atomicity (all or nothing), Consistency (valid state transitions), Isolation (independent transactions), and Durability (persisting committed updates).

CRUD

An acronym representing the four basic functions of persistent storage: Create (INSERT), Read (SELECT), Update (UPDATE), and Delete (DELETE).

mysqli_connect()

A PHP function in the MySQLi extension that opens and establishes a connection to a running MySQL database server.

mysqli_select_db()

A PHP function that sets or changes the default active database for queries on an established MySQL connection.

mysqli_query()

A PHP function that performs a single SQL query against the currently active database on a specified connection.

mysqli_multi_query()

A PHP function that executes one or more SQL queries concatenated into a single string separated by semicolons.

mysqli_fetch_assoc()

A PHP function that retrieves a row of data from a result set and returns it as an associative array where column names serve as keys.

mysqli_fetch_row()

A PHP function that fetches one record from a database result set as an enumerated (numeric) array indexed starting at $0$.

mysqli_num_rows()

A PHP function that retrieves the total count of rows present in a result set produced by a SELECT query.

mysqli_affected_rows()

A PHP function that returns the total number of rows modified, inserted, or deleted by the most recently executed SQL statement.

Prepared Statements

A feature in MySQLi that separates SQL structure from user-provided data using parameter placeholders (?), preventing SQL injection vulnerabilities and optimizing repeated query execution.

mysqli_stmt_bind_param()

A PHP function used to bind application variables as parameters to the question mark placeholders in a prepared SQL statement.

mysqli_begin_transaction()

A PHP function that explicitly starts a new database transaction, grouping subsequent operations into a single ACID unit of work.

mysqli_commit()

A PHP function that commits the current database transaction, saving all modified records permanently to the database.

mysqli_rollback()

A PHP function that cancels the current transaction and reverts all modifications made within it, restoring the database to its pre-transaction state.

mysqli_error()

A PHP function that returns a descriptive string error message corresponding to the most recent failed MySQLi operation.

mysqli_close()

A PHP function that terminates an active MySQL server connection and releases allocated server and memory resources.