SQL Main Purpose Database data or storing, manipulating and retrieving data in databases.
SQL:SQL is a domain-specific language used in programming and designed for managing data held in a relational database management system, or for stream processing in a relational data stream management system.
Database TablesA database most often contains one or more tables. Each table is identified by a name
Example:Product or Services
Keep in Mind
- SQL Query NOT case sensitive
Semicolon after SQL Statements?Semicolon is the standard way to separate each SQL statement in database system.
Most Of Important SQL Command:
- INSERT INTO
- CREATE DATABASE
- ALTER DATABASE
- CREATE TABLE
- ALTER TABLE
- DROP TABLE
- CREATE INDEX
- DROP INDEX
what is select Command:The SELECT statement, which follows a consistent and specific format, begins with the SELECT keyword followed by the columns to be included in the format. If an asterisk (*) is placed after SELECT, this sequence is followed by the FROM clause that begins with the keyword FROM, followed by the data sources containing the columns specified after the SELECT clause. These data sources may be a single table, combination of tables, subquery or view.
Optional clauses may be added but are not mandatory, i.e., the WHERE clause that gives conditions for returning data, or the ORDER BY clause that sorts output with one or more of the specified columns.
SELECT SQL COMMAND EXAMPLE :
Select All Customer data Record using this sql command:
select * from customer;
This SQL Command Used to Sort customer table customer_firstname
select * from customer ORDER BY customer_firstnmae;
Database is Particular column name select using this method command line:
select customer_firstname,customer_email,customer_genter from customer;