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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.
Nottingham (/ˈnɒtɪŋəm/ (About this soundlisten) NOT-ing-əm) is a city and unitary authority area in Nottinghamshire, England. Part of the East Midlands region, it is 128 miles (206 km) north of London and 45 miles (72 km) northeast of Birmingham. To the west lies Derby, separated by the M1 motorway.
Nottingham has links to the legend of Robin Hood and to the lace-making, bicycle (notably Raleigh bikes) and tobacco industries. It was granted its city charter in 1897, as part of Queen Victoria's Diamond Jubilee celebrations. Nottingham is a tourist destination; in 2018, the city received the second highest amount of overnight visitors in the Midlands and the highest amount in the East Midlands.
In 2017, Nottingham had an estimated population of 329,200. The population of the city proper, compared to its regional counterparts, has been attributed to its historical and tightly-drawn city boundaries. The wider conurbation, which includes many of the city's suburbs, has a population of 768,638. It is the largest urban area in the East Midlands and the second-largest in the Midlands. Its Functional Urban Area, also the largest in the East Midlands, has a population of 919,484. The population of the Nottingham/Derby metropolitan area is estimated to be 1,610,000.
Its metropolitan economy is the seventh largest in the United Kingdom with a GDP of $50.9bn (2014).[12] The city was the first in the East Midlands to be ranked as a sufficiency-level world city by the Globalization and World Cities Research Network.
Nottingham's public transport system won awards prior to 2015, including the largest publicly owned bus network in England, and is also served by Nottingham railway station and the modern Nottingham Express Transit tram system.
It is also a major sporting centre and, in October 2015, was named 'Home of English Sport'. The National Ice Centre, Holme Pierrepont National Watersports Centre and Trent Bridge international cricket ground are all based in or around the city, which is also the home of two professional football teams; the former world's oldest professional league club Notts County and Nottingham Forest, famously two-time winners of the UEFA European Cup under Brian Clough and Peter Taylor in 1979 and 1980. The city also has professional rugby, ice hockey and cricket teams, and the Aegon Nottingham Open, an international tennis tournament on the ATP and WTA tours. This accolade came just over a year after Nottingham was named as the UK's first City of Football.
On 11 December 2015, Nottingham was named a "City of Literature" by UNESCO, joining Dublin, Edinburgh, Melbourne and Prague as one of only a handful in the world. The title reflects Nottingham's literary heritage, with Lord Byron, D. H. Lawrence and Alan Sillitoe having links to the city, as well as a contemporary literary community, a publishing industry and a poetry scene.
The city is served by three universities: the University of Nottingham, Nottingham Trent University and the University of Law; hosting the highest concentration of higher education providers in the East Midlands.
