How to connect to SQL server :-
-----------------------------
- To connect to SQL server open SSMS and enter   following details.

	server type : DB Engine
	server name : LAPTOP-R82J1IA9
	authentication types : SQL server / windows
	login		: SA (system admin)
	password	: 123 (any password)
- SQL server authentication needs to prodive login   & password.
- by default Login contains SA as username.
- password is set during installation process.


Creating database in SQL server:-
-------------------------------
- In Object explorer
	select Databases => New Database
	Enter Databases Name => DB10
- click OK
- A Database is created with following two files
	 1 - Data file (.MDF)
	 2 - Log file (.LDF)
- file extention
	.MDF(master data file)
	.LDF(log data file)
- Data file stores data and log files stores operation.

NAME     |  TYPE | INITIAL SIZE |  AUTOGROWTH |  PATH
DB10	 |  Data |   8MB	|   64MB      |  ----
DB10_LOG |   LOG |   8MB        |   64MB      |  ------

path :-
-----

C:\Program Files\
   Microsoft SQL Server\
   MSSQL15.MSSQLSERVER\MSSQL\DATA


=======================================
	 
		T-SQL (Transact-SQL)
		--------------------
=> SQL stands for Structured query language.
=> Used to communicate with SQL server.
=> User communicates with SQL server by sending    commands called Queries.
=> A Query is command/instructions/questions submitted    to SQL server to perform some operaton over DB.
=> SQL is originally introduced by IBM and initial name    of this language was SEQUEL and later it is renamed    to SQL
=> SEQUEL (Structured English Query Language).

user uses => SSMS =>to connect SQL server => to communicate with DB
 
=> Based on operations over DB SQL is categorized into following sub-languages.
	DDL (Data Defination Language) ,
	DML (Data Manipulation Language),
	DRL (Data Retrival Language),
	TCL (Transaction Control Language),
	DCL (Data Control Language)


			SQL
			---


   DDL	|  DML	|  DRL	  | TCL	    |    DCL   |
create	  insert   select  commit	grant
alter	  update	   rollback	revoke
drop	  delete	   savepoint
truncate  merge


Data & Data Defination :
-----------------------
- Data Defination is also called MetaData which means data about the data.

EMPID   ENAME    SAL  => DATA DEFINATION/METADATA
100       A      5000 => DATA


Data Types  in SQL Server:-
-------------------------
=> Data types specifies
	- type of the data allowed in a column.
	- amount of memory allocated for column.