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Creation-Date: 2011-10-17T00:43:21+08:00
====== mysql ======
Created Monday 17 October 2011
MySQL Tutorial: Install, Create DB and Table, Insert and Select Records
This MySQL jumpstart guide will get you running quickly on the basics. This explains how to install MySQL, create a sample database, create a table, insert records into the table, and select records from the table.
===== 1. Install and Configure MySQL =====
Go to the MySQL download page, and select your appropriate platform to download the latest version of MySQL community server.
* If you are installing on RedHat based distro (for example: CentOS), follow this article: Install MySQL on Linux using rpm
* You can also use yum groupinstall to install the MySQL Database group.
* If you want to install MySQL along with the other components of the LAMP stack (Apache, and PHP), follow this article: How to install or upgrade LAMP
===== 2. Create MySQL Database =====
Once MySQL is installed, connect to it using MySQL root user and create the database as shown below.
**# mysql -u root -p**
**Enter password:**
**mysql>**
After connecting as MySQL root user, execute the following command from the “mysql> ” prompt to create a database.
The following command will create the database called “thegeekstuff”.
**mysql> create database thegeekstuff**
Use “show databases” command to verify that the database was created successfully.
**mysql> show databases;**
**+--------------------+**
**| Database |**
**+--------------------+**
**| information_schema |**
**| mysql |**
**| thegeekstuff |**
**+--------------------+**
**3 rows in set (0.00 sec)**
===== 3. Create MySQL Table =====
**Connect **to the newly created database using “use” command before you can perform any operation in the database.
To connect to the database, do the following.
**mysql> use thegeekstuff;**
**Database changed**
The following example creates a employee table.
**create table employee (**
**id INT AUTO_INCREMENT PRIMARY KEY,**
**name varchar(20),**
**dept varchar(10),**
**salary int(10)**
**)**__;__
When you copy-paste the above create table command in the “mysql> ” prompt, it will display the continuation prompt “->” starting from the 2nd line, which indicates that the command is still not over. The end of a SQL command is identified by a **semi-colon**.
**mysql> create table employee (**
** -> id INT AUTO_INCREMENT PRIMARY KEY,**
** -> name varchar(20),**
** -> dept varchar(10),**
** -> salary int(10)**
** -> );**
**Query OK, 0 rows affected (0.00 sec)**
You can also use any one of the following data types.
* dcode** SMALLINT**
* mcode **MEDIUMIN**
* project_start **DATE**
* loggedon** TIME**
Do the following to view all the tables available in the database.
**mysql> show tables;**
**+------------------------+**
**| Tables_in_the geekstuff |**
**+------------------------+**
**| employee |**
**+------------------------+**
**1 row in set (0.00 sec)**
To view the table //description,// do the following.
**mysql> desc employee;**
**+--------+-------------+------+-----+---------+----------------+**
**| Field | Type | Null | Key | Default | Extra |**
**+--------+-------------+------+-----+---------+----------------+**
**| id | int(11) | NO | PRI | NULL | auto_increment |**
**| name | varchar(20) | YES | | NULL | |**
**| dept | varchar(10) | YES | | NULL | |**
**| salary | int(10) | YES | | NULL | |**
**+--------+-------------+------+-----+---------+----------------+**
**4 rows in set (0.01 sec)**
===== 4. Insert Records into a Table =====
Use the following sample insert commands to insert some records to the employee table. While inserting values to //all //the columns in the table, you dont need to specify the column name. Just specify the values in the same sequence as the column names.
**insert into employee values(100,'Thomas','Sales',5000);**
**insert into employee values(200,'Jason','Technology',5500);**
**insert into employee values(300,'Mayla','Technology',7000);**
**insert into employee values(400,'Nisha','Marketing',9500);**
**insert into employee values(500,'Randy','Technology',6000);**
To insert values only to specific columns, you should specify the// column names //as shown below.
**mysql> insert into employee(name,dept) values('Ritu', 'Accounting');**
**Query OK, 1 row affected (0.01 sec)**
Note: You can also upload data from a text file to MySQL database using **mysqlimport **command.
===== 5. Query Records from a Table =====
To view all the records from a table, use the following select statement.
http://www.thegeekstuff.com/2011/10/mysql-tutorial-basics/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+TheGeekStuff+%28The+Geek+Stuff%29
**mysql> select * from employee;**
**+-----+--------+------------+--------+**
**| id | name | dept | salary |**
**+-----+--------+------------+--------+**
**| 100 | Thomas | Sales | 5000 |**
**| 200 | Jason | Technology | 5500 |**
**| 300 | Mayla | Technology | 7000 |**
**| 400 | Nisha | Marketing | 9500 |**
**| 500 | Randy | Technology | 6000 |**
**| 501 | Ritu | Accounting | NULL |**
**+-----+--------+------------+--------+**
**6 rows in set (0.00 sec)**
To view only a specific columns from a table, specify the column names in the select command.
**mysql> select name, dept from employee;**
The following select statement has a where condition which displays the employee records who belong to Technology department and getting a salary >= 7000.
**mysql> select * from employee where dept = 'Technology' and salary >= 6000;**
**+-----+--------+------------+--------+**
**| id | name | dept | salary |**
**+-----+--------+------------+--------+**
**| 300 | Mayla | Technology | 7000 |**
**| 500 | Randy | Technology | 6000 |**
**+-----+--------+------------+--------+**
**2 rows in set (0.00 sec)**