Database (Increase, delete, change, check)

Database:
Three levels: File--Service--Interface (DBMS)
Two ways to sign in: Windows identity logon; SQL Server identity login.
How do I set up SQL Server authentication?
1. Object Explorer Right-click-Properties--Security--sqlserver and Windows identity login.
2. Object Explorer--security--Login--sa--Right click--Properties--general--Set password
3. Object Explorer--security--Login--sa--Right click--Properties--state--grant, enable
Restart the database service.

How do I create a new database?
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. ldf--Log Files
. mdf--Master Data File
. ndf--Secondary data files
In a database, you can have multiple log files, multiple secondary data files, but only one master data file.

How do I create a new table?
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Row order independent, column order independent.

SQL statement DDL DML (add, delete, change, check) DCL

Increase
Insert into table name (column name, column name, column name,...) VALUES (value, value, value,....)
Insert into table name values (value, value, value, value): )

Check
First, simple query
SELECT * FROM table name
Select column name, column name, ... from table name--Projection
Equivalence and non-equivalence query
SELECT * FROM table name where column name = value-equivalent query
Non-equivalent query
SELECT * FROM table name where column name <> value
SELECT * FROM table name where column name > value >=
SELECT * FROM table name where column name < value <=

Multi-Conditional query logic with (and), logical OR (OR)
SELECT * FROM table name where Condition 1 and condition 2 ...
SELECT * FROM table name where Condition 1 or condition 2 ...
If, in the where filter condition, both and and or are present, the and is first calculated. Unless you use parentheses to change the priority
First class.

Range query.
SELECT * from Car where price >=30 and price<=50
SELECT * from Car where price between and 50

SELECT * from Car where oil=7.4 or oil=8.5 or oil=9.4
SELECT * from Car where oil in (7.4,8.5,9.4)

Fuzzy query. Generally not used =, but with like
%--any number of arbitrary characters
_--an arbitrary character
SELECT * from Car where Name like ' BMW% '
BMW%--starts with a BMW
% BMW--End with BMW
BMW%--as long as it contains the two words of BMW can.

The BMW%--represents the third character to start with a BMW.

To re-query:
Select DISTINCT column name from car--if there are duplicate values in the column, only 1 are checked out.

Sort
SELECT * FROM Car ORDER BY price asc--default is ascending ascending descending
SELECT * FROM car ORDER BY price DESC
SELECT * from Car ORDER by oil asc,price desc--oil main sort, price order

By deleting
Delete from car--all data
Delete from car where condition--the condition here is the same as the condition of select.

Change
Update table name set column name = value, column name = value ... where condition
Update Car Set price = Price + Price * 0.15 where Name is like ' BMW% '
Update car set name= ' 300C 3.5L commercial Vehicle ', oil= ' 9 ' where code= ' c012 '

Database (Increase, delete, change, check)