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Error : Your all database details is correct but the database is not connected  in any application.

Solution : The problem due the ” sql.safe_mode”  is “On” in php.ini file.  You need to turn off the sql.safe_mode in server  php.ini file

sql.safe_mode = Off

Done

Database Connection by using jsp page .

The URL based mysql connection  is

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jdbc:mysql://serverip address/DATABASENAME?user=USERNAME&password=PASSWORD

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OR

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<!– Database connection settings –>
<property name=”connection.driver_class”>com.mysql.jdbc.Driver</property>

<property name=”connection.url”>jdbc:mysql://localhost/database_name</property>
<property name=”connection.username”>databses_user</property>
<property name=”connection.password”>password</property>

<!– configuration pool via c3p0–>

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OR

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try {
   	Class.forName("com.mysql.jdbc.Driver").newInstance();
 	// here we are connecting to localhost, port 3306.  Change it to your db server address:port
 	con = DriverManager.getConnection("jdbc:mysql://localhost:3306/databaseName",
         	"root", "secret");
 	//or  con = DriverManager.getConnection("jdbc:mysql://localhost:3306/databaseName?user=
 		root&password=secret";
 }
 catch(Exception e){
 		System.out.println(e.getMessage());
 	}
=================================

If anyone has run into a situation where sql queries from your java app were erroring out because of letter case in tables and column names in MySQL database, I have a quick solution for you.

First, what you should have done, but probably was too creative and used mixed case for creating table names/columns was,

If going back and modifying code is too much, there is a quick fix for UNIX/Linux side. As the article above states, you need to set lower_case_table_names property to 1.

Simply create file /etc/my.cnf or if already created then only add the variable there thus:

[mysqld]
lower_case_table_names=1

Then restart the mysql service on the server.

As a result your java app will be able to query against MySQL tables and ignore letter case, the same way it does on Windows.

To login (from unix shell) use -h only if needed.

# [mysql dir]mysql  -u username -p

Create a database on the sql server.

mysql> create database [databasename];

List all databases on the sql server.

mysql> show databases;

Switch to a database.

mysql> use [db name];

To see all the tables in the db.

mysql> show tables;

To see database’s field formats.

mysql> describe [table name];

To delete a db.

mysql> drop database [database name];

To delete a table.

mysql> drop table [table name];

Show all data in a table.

mysql> SELECT * FROM [table name];

Returns the columns and column information pertaining to the designated table.

mysql> show columns from [table name];

Show certain selected rows with the value “whatever”.

mysql> SELECT * FROM [table name] WHERE [field name] = “whatever”;

Show all records containing the name “Bob” AND the phone number ‘3444444′.

mysql> SELECT * FROM [table name] WHERE name = “Bob” AND phone_number = ‘3444444′;

Show all records not containing the name “Bob” AND the phone number ‘3444444′ order by the phone_number field.

mysql> SELECT * FROM [table name] WHERE name != “Bob” AND phone_number = ‘3444444′ order by phone_number;

Show all records starting with the letters ‘bob’ AND the phone number ‘3444444′.

mysql> SELECT * FROM [table name] WHERE name like “Bob%” AND phone_number = ‘3444444′;

Show all records starting with the letters ‘bob’ AND the phone number ‘3444444′ limit to records 1 through 5.

mysql> SELECT * FROM [table name] WHERE name like “Bob%” AND phone_number = ‘3444444′ limit 1,5;

Use a regular expression to find records. Use “REGEXP BINARY” to force case-sensitivity. This finds any record beginning with a.

mysql> SELECT * FROM [table name] WHERE rec RLIKE “^a”;

Show unique records.

mysql> SELECT DISTINCT [column name] FROM [table name];

Show selected records sorted in an ascending (asc) or descending (desc).

mysql> SELECT [col1],[col2] FROM [table name] ORDER BY [col2] DESC;

Return number of rows.

mysql> SELECT COUNT(*) FROM [table name];

Sum column.

mysql> SELECT SUM(*) FROM [table name];

Join tables on common columns.

mysql> select lookup.illustrationid, lookup.personid,person.birthday from lookup left join person on lookup.personid=person.personid=statement to join birthday in person table with primary illustration id;

Creating a new user. Login as root. Switch to the MySQL db. Make the user. Update privs.

# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO user (Host,User,Password) VALUES(‘%’,'username’,PASSWORD(‘password’));
mysql> flush privileges;

Change a users password from unix shell.

# [mysql dir]/bin/mysqladmin -u username -h hostname.blah.org -p password ‘new-password’

Change a users password from MySQL prompt. Login as root. Set the password. Update privs.

# mysql -u root -p
mysql> SET PASSWORD FOR ‘user’@'hostname’ = PASSWORD(‘passwordhere’);
mysql> flush privileges;

Recover a MySQL root password. Stop the MySQL server process. Start again with no grant tables. Login to MySQL as root. Set new password. Exit MySQL and restart MySQL server.

# /etc/init.d/mysql stop
# mysqld_safe –skip-grant-tables &
# mysql -u root
mysql> use mysql;
mysql> update user set password=PASSWORD(“newrootpassword”) where User=’root’;
mysql> flush privileges;
mysql> quit
# /etc/init.d/mysql stop
# /etc/init.d/mysql start

Set a root password if there is on root password.

# mysqladmin -u root password newpassword

Update a root password.

# mysqladmin -u root -p oldpassword newpassword

Allow the user “bob” to connect to the server from localhost using the password “passwd”. Login as root. Switch to the MySQL db. Give privs. Update privs.

# mysql -u root -p
mysql> use mysql;
mysql> grant usage on *.* to bob@localhost identified by ‘passwd’;
mysql> flush privileges;

Give user privilages for a db. Login as root. Switch to the MySQL db. Grant privs. Update privs.

# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO user (Host,Db,User,Select_priv,Insert_priv,Update_priv,Delete_priv,Create_priv,Drop_priv) VALUES (‘%’,'databasename’,'username’,'Y’,'Y’,'Y’,'Y’,'Y’,'N’);
mysql> flush privileges;

or

mysql> grant all privileges on databasename.* to username@localhost;
mysql> flush privileges;

To update info already in a table.

mysql> UPDATE [table name] SET Select_priv = ‘Y’,Insert_priv = ‘Y’,Update_priv = ‘Y’ where [field name] = ‘user’;

Delete a row(s) from a table.

mysql> DELETE from [table name] where [field name] = ‘whatever’;

Update database permissions/privilages.

mysql> flush privileges;

Delete a column.

mysql> alter table [table name] drop column [column name];

Add a new column to db.

mysql> alter table [table name] add column [new column name] varchar (20);

Change column name.

mysql> alter table [table name] change [old column name] [new column name] varchar (50);

Make a unique column so you get no dupes.

mysql> alter table [table name] add unique ([column name]);

Make a column bigger.

mysql> alter table [table name] modify [column name] VARCHAR(3);

Delete unique from table.

mysql> alter table [table name] drop index [colmn name];

Load a CSV file into a table.

mysql> LOAD DATA INFILE ‘/tmp/filename.csv’ replace INTO TABLE [table name] FIELDS TERMINATED BY ‘,’ LINES TERMINATED BY ‘\n’ (field1,field2,field3);

Dump all databases for backup. Backup file is sql commands to recreate all db’s.

# [mysql dir]/bin/mysqldump -u root -ppassword –opt >/tmp/alldatabases.sql

Dump one database for backup.

# [mysql dir]/bin/mysqldump -u username -ppassword –databases databasename >/tmp/databasename.sql

Dump a table from a database.

# [mysql dir]/bin/mysqldump -c -u username -ppassword databasename tablename > /tmp/databasename.tablename.sql

Restore database (or database table) from backup.

# [mysql dir]/bin/mysql -u username -ppassword databasename < /tmp/databasename.sql

Create Table Example 1.

mysql> CREATE TABLE [table name] (firstname VARCHAR(20), middleinitial VARCHAR(3), lastname VARCHAR(35),suffix VARCHAR(3),officeid VARCHAR(10),userid VARCHAR(15),username VARCHAR(8),email VARCHAR(35),phone VARCHAR(25), groups VARCHAR(15),datestamp DATE,timestamp time,pgpemail VARCHAR(255));

Create Table Example 2.

mysql> create table [table name] (personid int(50) not null auto_increment primary key,firstname varchar(35),middlename varchar(50),lastnamevarchar(50) default ‘bato’);

MYSQL Statements and clauses

mysql_pconnect() will maintain a persistent connection to the database. Whenever your script calls the connect to database function, it first searches already existing connections to the database and if exists it will use the same connection to connect to the database, if not it will open a new connection to the database. ie. Connection is Persistent

where as mysql_connect() function will establish a new connection whenever a connection to database needed, and after executing the script, this function disconnects the connection. ie. connection is not a persistent one.

mysql_pconnect() function is used where your site has a Heavy Traffic and where as mysql_connect() function is used when there is moderate/less traffic to your site.

Update to latest Mysql version provided by cpanel

To upgrade the mysql on the cpanel server

* The best method to use the cpanel #/script/mysqlup to upgrade the mysql.

* To upgrade the mysql from 4.0.x to 4.1.x you need to enable the mysql upgrade in the whm under tweak setting

/scripts/upcp –force

/scripts/mysqlup –force

How to connect to Database for any user through Server

# mysql -u DBNAME -p DBPASS

command for taking  mysql backup:=>

#mysqldump databasename > file.sql

command for restoring : =>

# mysql -u [username] -p[password] [database] < [backup_file]

or

#mysql database name < file.sql