SET NOCOUNT ON

SET NOCOUNT ON

Advantages of   SET NOCOUNT ON – SQL Statement are

• (It prevents the sending of after process messages to the clients for each of SQL DML or DDL statements executed in a stored procedure.  Actually stored procedures that contain several statements that do not return much actual data, Hence setting above SQL statement to ON can boost the performance as well as Network traffic between clients machines and Server is greatly reduced

• It will reduce another query to get the how many tables / records are updated once the SQL DML / DDL statements are executed. It will help us to boost the performance of the SQL server also

SQL - Structured Query Language

 

SQL

Structured Query Language and it also spell as Structured English Query Language (SEQUEL). The Main features of SQL are

•  SQL stands for structured Query language
•   SQL lets you access and manipulate databases
•   SQL is an ANSI (American National Standards Institute) Standard
•   SQL is a standard interactive and programming language for querying and modifying data and managing databases
•   SQL can execute queries against the database 
•   SQL ca set permissions on tables, procedures and views
•   SQL can create stored procedures in a database
•   The basis of SQL is RDBMS, it stands for Relational Database Management System
•  The data in RDBMS is stored in database objects called tables and tables is nothing a collection of related data entries which is present in columns and rows

The following SQL statement will select all the records in the Customers Table

SELECT * FROM CUSTOMERS

(SQL is not case sensitive)

SQL is divided into two parts:

(1) The Data Manipulation Language (DML)

(2) The Data Definition Language (DDL)

The Main DML statements are given below

(1) SELECT
(2) UPDATE
(3) DELETE
(4) INSERT INTO
(5) SELECT INTO

The DDL part of SQL permits database tables to be created or deleted. It also defines indexes (keys), specified links between tables, and imposes constraints between tables. 

The most important DDL statements are given below
(1) Create Database
(2) Alter Database
(3) Create Table
(4) Alter Table
(5) Create INDEX
(6) Drop Index
(7) Drop table
(8) Drop Database


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SQL Select Statement

SELECT statement is used to select data from a database

The result is stored in a result table, called result-set

Syntax of the SQL Select Statement is

SELECT COLUMN_NAME FROM TABLE_NAME

for example.,

(1) SELECT * FROM CUSTOMERS: Selecting complete list of records and columns

CUST_ID	CUST_NAME
CUST001	ASHWIN

(2) SELECT CUST_ID FROM CUSTOMERS: Selecting complete list of records with only cust_id column

CUST_ID
CUST001

 (3) SELECT DISTINCT PERSON_NAME FROM PERSONS

Persons Table is as follows

ID	PERSON_NAME	Address	City	Mobile
1	Sachin	10th Main Road	Mumbai	9845012345
2	Henry	11th Main Road	Bengaluru	9945012345
3	Sachin	8th Main Road	Mumbai	9845012345

Now ABOVE query will get you

PERSON_NAME

SACHIN

HENRY

  

In above table one of records is having duplicate values. If we need to display or extract only different values or the records, we can use "Select Distinct statement"

 

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 Creating Database

CREATE DATABASE <<DATABASE_NAME>>

If we want to create the database  of customers

CREATE DATABASE CUSTOMERS

 Now the DATABASE OF CUSTOMERS will be created....