SQL is a standard language for storing, manipulating and retrieving data in databases. Our SQL tutorial will teach you how to use SQL in: MySQL, SQL Server, MS Access, Oracle, Sybase, Informix, Postgres, and other database systems.
SQL lets you access and manipulate databases SQL became a standard of the American National Standards Institute (ANSI) in 1986, and of the International Organization for Standardization (ISO) in 1987
SQL (Structured Query Language) is a domain-specific language used in programming and designed for managing data held in a relational database management system (RDBMS), or for stream processing in a relational data stream management system (RDSMS). It is particularly useful in handling structured data, i.e. data incorporating relations among entities and variables. SQL offers two main advantages over older read–write APIs such as ISAM or VSAM. Firstly, it introduced the concept of accessing many records with one single command. Secondly, it eliminates the need to specify how to reach a record, e.g. with or without an index.
Originally based upon relational algebra and tuple relational calculus, SQL consists of many types of statements, which may be informally classed as sublanguages, commonly: a data query language (DQL), a data definition language (DDL), a data control language (DCL), and a data manipulation language (DML). The scope of SQL includes data query, data manipulation (insert, update and delete), data definition (schema creation and modification), and data access control. Although SQL is essentially a declarative language (4GL), it also includes procedural elements.
SQL was one of the first commercial languages to use Edgar F. Codd’s relational model. The model was described in his influential 1970 paper, "A Relational Model of Data for Large Shared Data Banks". Despite not entirely adhering to the relational model as described by Codd, it became the most widely used database language.
SQL became a standard of the American National Standards Institute (ANSI) in 1986, and of the International Organization for Standardization (ISO) in 1987. Since then, the standard has been revised to include a larger set of features. Despite the existence of standards, most SQL code requires at least some changes before being ported to different database systems.
➲ SQL can execute queries against a database
➲ SQL can retrieve data from a database
➲ SQL can insert records in a database
➲ SQL can update records in a database
➲ SQL can delete records from a database
➲ SQL can create new databases
➲ SQL can create new tables in a database
➲ SQL can create stored procedures in a database
➲ SQL can create views in a database
➲ SQL can set permissions on tables, procedures, and views
☑ Oracle 12c
☑ MySQL
☑ Microsoft SQL Server
☑ PostgreSQL
☑ MongoDB
☑ MariaDB
☑ DB2
☑ SAP HANA
☑ InterBase
☑ OrientDB
☑ SQLite
☑ Cassandra
☑ CouchDB
☑ DynamoDB
☑ Neo4j
☑ Firebird
Now that you are familiar with what SQL is, let’s take a look at its imperative advantages for data collection, storing and manipulation, etc.
SQL generally operates at a high speed when users explore the database. It helps in retrieving large amounts of data quickly and efficiently.
SQL is highly user friendly, i.e. it is easy to use. Someone with no coding experience can easily learn basic SQL coding within a few days. The code structure is also simple, borrowing heavily from English sentences with minimal use of special characters.
With SQL, it is very easy to view and manipulate the existing data on the database. With a few queries, users can update or change the uploaded information on the database, thus making it helpful for storing dynamic information.
Among other uses of SQL, it is used for sorting and filtering data by using several queries, making the data more relevant and useful, while reducing redundancy. Under the uses of SQL or MySQL, it is integrally applied to maintain their database. Thus, it becomes easier to navigate if the users are familiar with SQL.
SQL is widely considered a safe and protected database. The system is password protected on every device, thus making it difficult for malicious users to use the data without consent.
SQL is highly-reliable to deliver correct results on complex queries by users, as compared to other Database Management systems.
SQL has a wide range of applications in today’s world. Being one of the most basic Database Management systems, SQL is a pathway language for students who wish to pursue Database Management. It also has many applications, like MySQL, Ingres, Oracle, Skybase and others. Here are some of the primary uses of SQL:
Amongst the prominent uses of SQL, it is applied as Data Definition Language (DDL) in order to define and modify the structure of data. The commands under DDL are used to add, remove or modify the tables within a database. Create, Drop, Alter, are some of the commonly used DDLs. Further, using DDL, anyone can independently curate a database and structure it as well as utilise and discard it at the end.
When SQL is applied as a Data Control Language, it is mainly to control the permissions and rights to perform certain actions on the database. When it comes to the uses of this SQL sub-language, it is mainly utilised by the Database Administrator to give or take back permission from the users. “Grant” and “Revoke” are examples of DCL. Further, the uses of SQL with this sub-language is to secure the database against misuse or corruption.
DML refers to the SQL commands used to make changes within the database. These are used to insert, edit or delete the existing data, even up to a single cell or entry. Some examples of DML are “Insert”, “Update”, ”Delete”. When it comes to the uses of SQL as DML, it simply corresponds to its ability to maintain an already existing database by entering more chunks of data and modifying, extracting and storing it.
n order to support the client/server architecture, SQL is applied as a Client-Server language to build a connection between the front-end and back-end and thus lending assistance to the design. Amongst the various uses of SQL, it can also be utilised as a part of the three-tier architecture pertaining to a client, an application and a database and this way it gives a clear structure to the Internet architecture.