Search the Lexicon
4 of 4 terms found
CRUD
CRUD stands for Create, Read, Update, and Delete, representing the four basic operations for persistent storage that nearly every data-driven application implements. In web development, CRUD operations map to HTTP methods (POST for Create, GET for Read, PUT/PATCH for Update, DELETE for Delete) and SQL statements (INSERT, SELECT, UPDATE, DELETE). Understanding CRUD is fundamental to building any application that stores data.
SQL Injection
SQL injection is a code injection attack where malicious SQL statements are inserted into input fields, potentially allowing attackers to read, modify, or delete database data, bypass authentication, or even execute system commands. It exploits applications that concatenate user input directly into SQL queries instead of using parameterized queries or prepared statements.
query
A query is a request to a database to retrieve, insert, update, or delete data. In web and mobile development queries are usually SQL statements such as SELECT, INSERT, UPDATE and DELETE that return a result set or an execution status. Important considerations include how parameters are passed (e.g. parameterized queries), performance (indexes, joins, LIMIT, pagination) and security risks like SQL injection. MySQL is a client-server database with richer concurrency features; SQLite is an embedded database commonly used on devices with different constraints and optimizations.