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SQL
SQL Meaning
SQL (Structured Query Language)is a specialized programming language designed for managing and manipulating data stored in relational databases. It allows users to perform various operations such as querying, updating, inserting, and deleting data efficiently12.
Key Principles of SQL
Declarative Language: SQL is a declarative language, meaning it specifies what data to retrieve or manipulate rather than how to perform the operation. This makes it easier to use and understand1.
Standardization: SQL became a standard of the American National Standards Institute (ANSI) in 1986 and the International Organization for Standardization (ISO) in 19872.
Components: SQL consists of several sublanguages, including Data Query Language (DQL), Data Definition Language (DDL), Data Control Language (DCL), and Data Manipulation Language (DML)1.
Common SQL Commands
SELECT: Retrieves data from a database.
INSERT: Adds new records to a database.
UPDATE: Modifies existing records.
DELETE: Removes records from a database.
CREATE: Creates new database objects like tables and views.
ALTER: Modifies existing database objects.
Example of a Simple SQL Query
SELECT*FROMCustomersWHERECustomerNameLIKE'J%'ORDER BYCustomerIDDESCLIMIT 10;
This query retrieves the top 10 customers whose names start with 'J', ordered in descending order by their customer ID3.
Uses of SQL
SQL is widely used across various industries and applications, including:
Data Retrieval: Extracting data from databases for analysis and reporting.
Data Manipulation: Adding, updating, and deleting data in databases.
Data Definition: Defining the structure and organization of data in databases.
Access Control: Managing user permissions and ensuring data security23.
Important Considerations
Interoperability: SQL implementations can vary between different database systems, leading to compatibility issues1.
Security: SQL injection is a common security vulnerability where malicious SQL code is inserted into queries to manipulate or corrupt data3.
In conclusion, SQL is a powerful and versatile language for managing relational databases, offering a wide range of functionalities for data manipulation, retrieval, and security12.
The Metropolitan Borough of Rotherham is a metropolitan borough of South Yorkshire, England. It is named after its largest town, Rotherham, but also spans the outlying towns of Maltby, Swinton, Wath-upon-Dearne, Dinnington and also the villages of Rawmarsh and Laughton. A large valley also spans the entire borough. Locally known as the Rother Valley.
The district was formed on 1 April 1974, under the Local Government Act 1972, as a merger of the County Borough of Rotherham, with Maltby, Rawmarsh, Swinton and Wath-upon-Dearne urban districts along with Rotherham Rural District and Kiveton Park Rural District.
Rotherham Metropolitan Borough Council is one of the safest Labour councils in the United Kingdom, although the number of Labour council seats dropped from 92% to 79% in 2014 following the Rotherham child sexual exploitation scandal.[2]
