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Using the Database




    Creating a database has no effect on which database currently is selected as the default database.  To make the new database the default database, issue a USE statement:  


USE my_db; 


After a database has been created, it can be populated with objects such as tables or stored routines.  The CREATE statement for tables is discussed in a later chapter. 


Displaying Database Structure 


The easiest way to display the database structure (as far as the database container) is to issue a SHOW CREATE DATABASE command. This command shows the  CREATE DATABASE statement that was used to create  the database (or could be used to recreate the database structure):  


mysql> SHOW CREATE DATABASE my_db\G 
************************* 1. row ************************* 
       Database: my_db 
       Create Database: CREATE DATABASE `my_db` 
                 /*!40100 DEFAULT CHARACTER SET utf8 COLLATE utf8_danish_ci */


Note: SCHEMA can be interchanged with DATABASE to perform the above statements. (i.e., CREATE SCHEMA mydb;) 




Problems 


            When a CREATE DATABASE command fails, the two most common problems are insufficient or incorrect permissions, or an attempt to create a database that already exists. 
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