What is the SQL language What is the SQL language

1.SQL Overview.

SQL is a general data processing language specification for databases, which can complete the following types of functions: extracting query data, inserting, modifying, deleting data, generating, modifying, and deleting database objects, database security control, database integrity and data protection control.

Refers to the language that computers can understand to interact with databases.

SQL is a Structured Query Language, which is a set of specialized program commands that accomplish the following tasks:

Retrieve data in one or more tables in one or more databases.

Manipulate the data in the table by inserting, deleting, or changing records.

Perform mathematical statistics on the data in the table.

Create, change, or delete tables in a database (access databases only) Create or delete indexes in a table.

The main structure of SQL query language is as follows:

select query field from table name where query condition statement [sort statement or grouping statement].

Query fields must be separated by a comma or replaced with an asterisk.

SQL Language: a structured query language. (structuredquerylanguage), which is the standard language for relational database management systems.

It is an interpretive language: write a sentence and execute a sentence, without the need for overall compilation and execution.

Grammatical features:1.There is no '', the string uses ''Contain.

2.There is no logical equality, and both assignment and logical equality are =

3.The type is no longer the most restrictive. Any data can be included in ''Within.

4.There is no concept of bool value, but in the view you can enter true false5It also has relational operators: > It returns a bool value.

6.It also has logical operators:! (not)&&and)||or)7.It is not case sensitive.

Structured Query Language is a high-level, non-procedural programming language that allows users to work on high-level data structures. It does not require the user to specify the storage method of the data, nor does it require the user to understand the specific data storage method, so different database systems with completely different underlying structures can use the same structured query language as the interface for data input and management. Structured Query Language statements can be nested, which makes it extremely flexible and powerful.

SQL is a powerful database language.

SQL (StructuredQueryLanguage) is a powerful database language. SQL is commonly used for database communication. ANSI (American National Standards Institute) claims that SQL is the standard language for relational database management systems.

SQL statements are often used to perform database operations, such as updating data in the database or retrieving data from the database. Common relational database management systems that use SQL include Oracle, Sybase, Microsoft SQLSer, Access, and Ingres.

While the vast majority of database systems use SQL, they do have their own proprietary extensions for their systems.

However, standard SQL commands such as:"select"、"insert"、"update"、"delete"、"create"with"drop"It is often used to complete the vast majority of database operations.

However, unlike other languages such as C, Pascal, etc., SQL does not have a loop structure (e.g., if-then-else, do-while), function definitions, and so on. And SQL only has a fixed set of data types, in other words, you can't create your own data types when using other programming languages.

SQL is powerful, but in a nutshell, it can be broken down into the following groups:

Data ManipulationLanguage (DML): used to retrieve or modify data.

DDL (DataDefinitionLanguage): used to define the structure of data, such as creating, modifying, or deleting database objects.

DCL (DataControlLanguage): This parameter defines the permissions of database users.

SQL Structured Query Language is a database query and programming language for accessing data and querying, updating, and managing relational database systems. Simply put, it's a database management language.

SQL (Structured Query Language) The main function of the SQL language is to establish contacts and communicate with various databases. According to ANSI (American National Standards Institute), SQL is the standard language for relational database management systems.

SQL statements can be used to perform a variety of operations, such as updating data in the database, extracting data from the database, and so on. The vast majority of popular relational database management systems use the SQL language standard. Although many databases have redeveloped and extended SQL statements, standard SQL commands including select, insert, update, delete, create, and drop can still be used to perform almost all database operations.

And the SQL you are talking about is a database language, which is used to count and manipulate databases. As for what to learn, your current question is equivalent to saying that you have to go to a place, you can get to it by walking, you can get to it by bicycle, you can get there by taxi.

Structured Query Language, full name, is used to count and manipulate databases.

Full name: SQL Structured Query Language

It can be divided into: DCL Data Creation Language, DML Data Manipulation Language is the most commonly used.

ddl data definition language。。。

What is SQL?

SQL stands for Structured Query Language.

SQL lets you access and work with databases.

SQL is a computer language based on ANSI (American National Standards Institute).

from-Sloth Academy-Free data knowledge learning platform.