You can use sql server to: 1. Query data from the database; 2. Retrieve data from the database, or insert new data into the data; 3. Update data in the database and delete data from the database data; 4. Create a new database, create a new table, create a stored procedure, and create a view; 5. Set the permissions of tables, stored procedures, and views.
#SQL Server is a relational database management system launched by Microsoft. It has the advantages of ease of use, good scalability and a high degree of integration with related software, and can be used across a variety of platforms ranging from laptops running Microsoft Windows 98 to large multi-processor servers running Microsoft Windows 2012.
Microsoft SQL Server is a comprehensive database platform that provides enterprise-class data management using integrated business intelligence (BI) tools. The Microsoft SQL Server database engine provides more secure and reliable storage capabilities for relational and structured data, allowing you to build and manage highly available and high-performance data applications for your business.
What is the use of learning sql server?
You can use sql server to query data from the database, retrieve data from the database, or insert new data into the data. data; you can also update data in the database and delete data in the database, create new databases, create new tables, create stored procedures, create views, and you can set permissions on tables, stored procedures and views.
#The SELECT statement is used to select data from the database, and its results are stored in a result table, also called a result set. Note: SQL Server is case insensitive and SELECT and select are the same. There is also the issue of semicolons, which in other database systems may require a semicolon at the end of each statement; semicolons are the standard way to separate each SQL Server statement in database systems, so that they can be The server executes more SQL statements in the same request.
As shown below is the SQL query statement, and the queried data can be seen:
We not only need to be able to type code by hand, And you have to learn to write code by hand, so remember some important SQL commands, such as: SELECT - extract data from the database; UPDATE - update data in the database; DELETE - delete data from the database; INSERT INTO - insert new data into the database Data; CREATE DATABASE - create a new database; ALTER DATABASE - modify the database; CREATE TABLE - create a new table; ALTER TABLE - change the table in the database; DROP TABLE - delete the table; CREATE INDEX - create an index; DROP INDEX - delete the index. In this way, no matter which company we go to for an interview, we will not have a headache when it comes to such database questions, so we must learn to write code by hand.
Every time you change the data table in the database and insert new values, you must remember to refresh the database and update the data table in the Model. If you do not update, you will not get the data we want. Before updating, delete the original table first, and then update the model from the database
First, right-click on the blank space and the following prompt box will pop up, and you can perform the following operations, that is, in Visual Studio 2015 Just click in the Models to delete the model, and then update the model from the database.
As shown in the figure below:
Views in the database can be used as tables. For example, our permissions can create their own views by creating views. Permissions and other operations, etc.
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