Archive for September, 2010
Shell Script in 5 minutes!
Shell scripts are short programs that are written in a shell programming language and interpreted by a shell process. They are extremely useful for automating tasks on Linux and other Unix-like operating systems.
1. Here is very short tutorials to make a very basic shell scripting.
. open vi or any other advance editor like vim
#!/bin/bash clear pwd echo "Hello phpmind, world." |
2. Save this script and give a name for example “phpmind.txt”
3. phpmind will be your command.
4. To run your command type ./phpmind
5. If its says Permission denied then use chmod 755 phpmind
6. Now the script is ready to run by typing the following, again while in the same directory, and then pressing the ENTER key:
./ phpmind
How It Works
The first of the three lines tells the operating system what shell to use to interpret the script and the location (i.e., absolute pathname) of the shell. The shell is bash, which is located in the /bin directory (as are all shells); thus the line contains /bin/bash. This instruction is always preceded by a pound sign and an exclamation mark in order to inform the operating system that it is providing the name and location of the shell (or other scripting language).
The second line tells the shell to issue the clear command. pwd (which shows the current directory),
The third line tells the shell to write the phrase Good morning, world. on the screen. It uses the echo command, which instructs the shell to repeat whatever follows it.
How to debug PHP code?
Debugging PHP code is challenging task for all Php developers, however some simple php debugging techniques can help you to code faster and thus save very valuable coding time.
Enable Notices on development servers!
A notice is a type of error message which is less severe than parse, fatal and warning error messages. A notice may tell you that you have used that variable without defining initialized it! Enabling notices helps you to do following things ….
- Warns about un-initialized variables and non-existent array indexes.
- Identifies deprecated behavior.
- Various non-critical issues that could potentially cause problems.
# Inside PHP.ini error_reporting = E_ALL # Inside httpd.conf or .htacess php_value error_reporting 2047 # Inside a script |
If you want to test that notices are turned on you can simply create a file with the following:
Here I would like to remind you that you should always ensure that the display_errors ini setting is set to ‘Off’ for any live/production sites.
Part from that PHP 5.0 introduces E_STRICT, which is primarily used to indicate functionality that has been deprecated in PHP5.
PHP 5.0 Error Reporting
# Inside PHP.ini error_reporting = E_ALL | E_STRICT # Inside httpd.conf or .htacess php_value error_reporting 4095 # Inside a script |
Use a Logging System
A logging system can be very useful in tracking down bugs, especially when they happen in a production environment. Such a system can also be useful in debugging during development. Users rarely report errors and often may not even notice the erroneous behavior. So it is absolutely critical to log errors to ensure that is a record of the problem.
# Inside PHP.ini error_log = /home/vhost/logs/php_error_log display_errors = Off log_errors_max_len = 0 |
As for all the other errors, we need to make sure that they are caught and dealt with properly. Make sure the user is shown a nice error page (with a suitably cute ‘oops-back-soon’ picture) and then log, log everything in sight!
The stack current trace (see debug_backtrace() and debug_print_backtrace()).
- The output of get_defined_vars(). However, this is only useful if you call it at the point the error occurs, not at the point the error is logged. This includes global variables.
- Any and all information about the remote user (IP address, user agent, session data)
- All global variable data (which includes the contents of $_COOKIES, $_SERVER etc.)
- Any other status data which is specific to your application
Use an Integrated Development Environment and Debugger
Use a editor with inbuilt live Php debug (Like Zend Studio, phped ,Phpdesigner, eclipse etc), Editors like editpad, notepad doesn’t support live debugging and thus need to run the php file on browser for finding the errors. These editors run php scripts via command line on every save and present any errors found.
I also use a remote debugger (ZendDebugger), which ties into the IDE. The remote debugger is a PHP module that allows you to debug code on your server using the IDE on your local machine. You can set breakpoints, inspect variables, examine stack traces, profile code and all the other benefits you would expect from a debugger. And no, Zend does not sponsor me.
Use Xdebug
The Xdebug extension allows you to find stack traces and function traces in error messages, memory allocation and protect from infinite recursions happening
It also provides profiling information for PHP code and is having the capability to debug scripts interactively with a debug client.
Use PHP Frameworks
Php frameworks like Zend, codeignitor and cakephp provides a lot of functionality for setting up test cases, units and debugging. Most of the code is ran via libraries the error messages are nicely crafted and provides inbuilt details.
Unit Testing
Unit testing may not be everyone’s idea of fun, but it I is very good for developing larger projects. It can give you confidence that code is fine, as well as point out problems before your code goes into production.
Error Tracking with magic constants
PHP has four magic constants, _FILE_, _LINE_, _FUNCTION_ and _CLASS_ that can be used to backtrack to the source of the problem.
Live HTTP Headers Tools?
Here is a list of mostly used debugging performance checking and HTTP troubleshooting tools. These software and tools can be used anywhere in any site.
- Use Charles HTTP Proxy for all my HTTP troubleshooting needs.
- Firefox Web Developer tools
- Firefox Live HTTP Headers Extension
- Use Fiddler2, which is a free, it is a highly configurable proxy; works with all browsers, allows header inspection/editing/auto modification on request/response.
- Ethereal it is used for troubleshooting, analysis, software and protocol development, and education. – It runs on all popular computing platforms, including Unix, Linux, and Windows.
- Wireshark – To view full HTTP headers and actions (get/post/).
Best PHP Jquery Plugins.
MySql frequently used commands?
MySQL is one of the best and globally used database. It will be good to learn the basic commands in Mysql to work interactively with the website and database servers. It is an GPL software as well as paid version is available with support. MySQL uses Structured Query Language (SQL-pronounced sequel), here i have listed mostly used commands for requesting information from a database. Mysql sends each SQL statement that you issue to the server to be executed. Because of its fast performance, reliability, ease of use, and versatility in working with programming languages NASA, FedEx, Yahoo other big php application are using mysql as backend.
This is a list of handy MySQL mysql-textboxs that I use time and time again. At the bottom are statements, clauses, and functions you can use in MySQL. Below that are PHP functions you can use to interface with MySQL.
Below when you see # it means from the unix shell. When you see mysql> it means from a MySQL prompt after logging into MySQL.
To login (from unix shell) use -h only if needed.
# [mysql dir]/bin/mysql -h hostname -u root -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 db (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 mysql-textboxs 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 | String Functions | Date and Time Functions |
| ALTER DATABASE
ALTER TABLE ALTER VIEW ANALYZE TABLE BACKUP TABLE CACHE INDEX CHANGE MASTER TO CHECK TABLE CHECKSUM TABLE COMMIT CREATE DATABASE CREATE INDEX CREATE TABLE CREATE VIEW DELETE DESCRIBE DO DROP DATABASE DROP INDEX DROP TABLE DROP USER DROP VIEW EXPLAIN FLUSH GRANT HANDLER INSERT JOIN KILL LOAD DATA FROM MASTER LOAD DATA INFILE LOAD INDEX INTO CACHE LOAD TABLE…FROM MASTER LOCK TABLES OPTIMIZE TABLE PURGE MASTER LOGS RENAME TABLE REPAIR TABLE REPLACE RESET RESET MASTER RESET SLAVE RESTORE TABLE REVOKE ROLLBACK ROLLBACK TO SAVEPOINT SAVEPOINT SELECT SET SET PASSWORD SET SQL_LOG_BIN SET TRANSACTION SHOW BINLOG EVENTS SHOW CHARACTER SET SHOW COLLATION SHOW COLUMNS SHOW CREATE DATABASE SHOW CREATE TABLE SHOW CREATE VIEW SHOW DATABASES SHOW ENGINES SHOW ERRORS SHOW GRANTS SHOW INDEX SHOW INNODB STATUS SHOW LOGS SHOW MASTER LOGS SHOW MASTER STATUS SHOW PRIVILEGES SHOW PROCESSLIST SHOW SLAVE HOSTS SHOW SLAVE STATUS SHOW STATUS SHOW TABLE STATUS SHOW TABLES SHOW VARIABLES SHOW WARNINGS START SLAVE START TRANSACTION STOP SLAVE TRUNCATE TABLE UNION UNLOCK TABLES USE |
AES_DECRYPT
AES_ENCRYPT ASCII BIN BINARY BIT_LENGTH CHAR CHAR_LENGTH CHARACTER_LENGTH COMPRESS CONCAT CONCAT_WS CONV DECODE DES_DECRYPT DES_ENCRYPT ELT ENCODE ENCRYPT EXPORT_SET FIELD FIND_IN_SET HEX INET_ATON INET_NTOA INSERT INSTR LCASE LEFT LENGTH LOAD_FILE LOCATE LOWER LPAD LTRIM MAKE_SET MATCH AGAINST MD5 MID OCT OCTET_LENGTH OLD_PASSWORD ORD PASSWORD POSITION QUOTE REPEAT REPLACE REVERSE RIGHT RPAD RTRIM SHA SHA1 SOUNDEX SPACE STRCMP SUBSTRING SUBSTRING_INDEX TRIM UCASE UNCOMPRESS UNCOMPRESSED_LENGTH UNHEX UPPER |
ADDDATE
ADDTIME CONVERT_TZ CURDATE CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP CURTIME DATE DATE_ADD DATE_FORMAT DATE_SUB DATEDIFF DAY DAYNAME DAYOFMONTH DAYOFWEEK DAYOFYEAR EXTRACT FROM_DAYS FROM_UNIXTIME GET_FORMAT HOUR LAST_DAY LOCALTIME LOCALTIMESTAMP MAKEDATE MAKETIME MICROSECOND MINUTE MONTH MONTHNAME NOW PERIOD_ADD PERIOD_DIFF QUARTER SEC_TO_TIME SECOND STR_TO_DATE SUBDATE SUBTIME SYSDATE TIME TIMEDIFF TIMESTAMP TIMESTAMPDIFF TIMESTAMPADD TIME_FORMAT TIME_TO_SEC TO_DAYS UNIX_TIMESTAMP UTC_DATE UTC_TIME UTC_TIMESTAMP WEEK WEEKDAY WEEKOFYEAR YEAR YEARWEEK |
| Mathematical and Aggregate Functions | Flow Control Functions/Command-Line Utilities | PHP API – using functions built into PHP with MySQL |
| ABS
ACOS ASIN ATAN ATAN2 AVG BIT_AND BIT_OR BIT_XOR CEIL CEILING COS COT COUNT CRC32 DEGREES EXP FLOOR FORMAT GREATEST GROUP_CONCAT LEAST LN LOG LOG2 LOG10 MAX MIN MOD PI POW POWER RADIANS RAND ROUND SIGN SIN SQRT STD STDDEV SUM TAN TRUNCATE VARIANCE |
CASE
IF IFNULL NULLIF Command-Line Utilities comp_err isamchk make_binary_distribution msql2mysql my_print_defaults myisamchk myisamlog myisampack mysqlaccess mysqladmin mysqlbinlog mysqlbug mysqlcheck mysqldump mysqldumpslow mysqlhotcopy mysqlimport mysqlshow perror |
mysql_affected_rows
mysql_change_user mysql_client_encoding mysql_close mysql_connect mysql_create_db mysql_data_seek mysql_db_name mysql_db_query mysql_drop_db mysql_errno mysql_error mysql_escape_string mysql_fetch_array mysql_fetch_assoc mysql_fetch_field mysql_fetch_lengths mysql_fetch_object mysql_fetch_row mysql_field_flags mysql_field_len mysql_field_name mysql_field_seek mysql_field_table mysql_field_type mysql_free_result mysql_get_client_info mysql_get_host_info mysql_get_proto_info mysql_get_server_info mysql_info mysql_insert_id mysql_list_dbs mysql_list_fields mysql_list_processes mysql_list_tables mysql_num_fields mysql_num_rows mysql_pconnect mysql_ping mysql_query mysql_real_escape_string mysql_result mysql_select_db mysql_stat mysql_tablename mysql_thread_id mysql_unbuffered_query |
What are the differences between absolute and relative positioning?
Absolute
This is a very powerful type of positioning that allows you to literally place any page element exactly where you want it. You use the positioning attributes top, left bottom and right to set the location. Remember that these values will be relative to the next parent element with relative (or absolute) positioning. If there is no such parent, it will default all the way back up to the element itself meaning it will be placed relatively to the page itself.
Most important thing about absolute positioning is that these elements are removed from the flow of elements on the page. An element with this type of positioning is not affected by other elements and it doesn’t affect other elements. This is a serious thing to consider every time you use absolute positioning.
<html>
<head>
<style type="text/css">
h2
{
position:absolute;
left:100px;
top:150px;
}
</style>
</head>
<body>
<h2>This is a heading with an absolute position</h2>
<p>With absolute positioning, an element can be placed anywhere on a page. The heading below is placed 100px from the left of the page and 150px from the top of the page.</p>
</body>
</html> |
Relative
This type of positioning is probably the most confusing and misused. What it really means is “relative to itself”.
A relative positioned element is positioned relative to its normal position. The content of a relatively positioned elements can be moved and overlap other elements, but the reserved space for the element is still preserved in the normal flow.
Relatively positioned element are often used as container blocks for absolutely positioned elements.
example -
<html>
<head>
<style type="text/css">
h2.pos_top
{
position:relative;
top:-50px;
}
</style>
</head>
<body>
<h2>This is a heading with no position</h2>
<h2 class="pos_top">This heading is moved upwards according to its normal position</h2>
<p><b>Note:</b> Even if the content of the relatively positioned element is moved, the reserved space for the element is still preserved in the normal flow.</p>
</body>
</html> |
What is New In MySQL 5.0?
MySQL is mostly used for web development in the Linux environment. Specially LAMP. It is the “M” in the acronym LAMP (Linux operating system, Apache web server, MySQL database, and Perl / PHP / Python scripting languages).
MySQL is usually described as open source. MySQL is actually available under both free and commercial licenses. MySQL is licensed under the GNU Public License (GPL).
Stored program objects are the most valuable significant upgrade to MySQL5.0.
A) Views
B) Stored Procedures
C) Functions
D) Triggers
Views
A view is a virtual table: a SELECT statement with a name. Microsoft SQL Server calls them views as well; Microsoft Access calls them queries. Selecting from the view name executes the underlying SELECT statement, and returns the results as columns in the virtual table. MySQL views may be read only or updateable. A check option can be specified to prevent views from being updated with rows that they cannot themselves SELECT
Disadvantage.
It is not possible to create an index on a view.
Subqueries cannot be used in the FROM clause of a view.
There is a general principle that you cannot modify a table and select from the same table in a subquery.
Example
CREATE VIEW view_name AS
SELECT column_name(s)
FROM table_name
WHERE condition
Stored procedures
Stored procedures are created via the CREATE PROCEDURE statement, and executed via the CALL statement. They may include input, output, and input-output parameters. MySQL stored procedures follow the SQL Server model, which permits a rowset to be returned simply by including a SELECT statement in the procedure. Unlike SQL Server, however, stored procedures in MySQL are not compiled. They do share many of the same advantages, such as standardizing code and reducing network traffic by performing business logic within the server.
Why use Stored Procedures?
Stored procedures are fast! It takes some advantage of caching, just as prepared statements do. There is no compilation, so an SQL stored procedure won’t work as quickly as a procedure written with an external language such as C.
2. Stored procedures are components! Suppose that you change your host language — no problem, the logic is in the database not the application.
3. Stored procedures are portable! When you write your stored procedure in SQL, you know that it will run on every platform that MySQL runs on, without obliging you to install an additional runtime-environment package.
4. Stored procedures are stored! If you write a procedure with the right naming conventions, for example saying chequing_withdrawal for a bank transaction, then people who want to know about chequing can find your procedure. It’s always available as ‘source code’ in the database itself.
5. Stored procedures are migratory! MySQL adheres fairly closely to the SQL:2003 standard. Others (DB2, Mimer) also adhere. Others (Oracle, SQL Server).
A stored procedure has a name, a parameter list, and an SQL statement, which can contain many more SQL statements. There is new syntax for local variables, error handling, loop control, and IF conditions. Here is an example of a statement that creates a stored procedure.
CREATE PROCEDURE procedure1 /* name */
(IN parameter1 INTEGER) /* parameters */
BEGIN /* start of block */
DECLARE variable1 CHAR(10); /* variables */
IF parameter1 = 17 THEN /* start of IF */
SET variable1 = 'birds'; /* assignment */
ELSE
SET variable1 = 'beasts'; /* assignment */
END IF; /* end of IF */
INSERT INTO table1 VALUES (variable1); /* statement */
END /* end of block */
What I’m going to do is explain in detail all the things you can do with stored procedures. We’ll also get into another new database object, triggers, because there is a tendency to associate triggers with stored procedures.
Triggers
Triggers are event-driven stored procedures. They are tied to a specific table, and to an event on that table (INSERT, UPDATE, or DELETE). When the event occurs, the trigger is executed (or “fired”.)
One key difference between MySQL triggers and those in SQL Server is that MySQL triggers can be called either before the triggering action or after it, whereas SQL Server triggers are after only. SQL Server does have an INSTEAD OF trigger not present in MySQL. Another key difference is the FOR EACH ROW syntax in MySQL, that will cause the trigger to execute for each row modified. The prefixes “OLD.” and “NEW.” enable the trigger body to reference columns before or after being modified. SQL Server triggers execute once per statement, and must take into account the possibility of multiple rows being affected.
Storage enhancements and tools
1. VARCHAR can store max of 65,532 bytes
2. There is a new BIT datatype.
3. MySQL’s architecture uses plug-in storage engines to implement the physical storage of database tables.
4. Each table may use a different storage engine.
5. The default storage engine, MyISAM, is very fast but does not have the ability to capture transactions.
6. InnoDB storage engine is good for transactions, and aslo provide row-level locking.
7. The InnoDB engine uses a more compact storage format than previously.
8. MySql 5.0 have new storage engine types to the product: Archive, and Federated
9. The Federated storage engine enables access to remote tables, similar to a linked server definition in Microsoft SQL Server.
10. MySql now includes a set of graphical user interfaces for common administration and development tasks.
- MySQL Instance Configuration Wizard – This tool is a step-by-step guide to configuring an instance of MySQL. Specifically, it creates the my.ini file, a text file containing startup configuration parameters.
- MySQL Query Browser – This tool can be used to build queries and test them. It’s similar to Query Analyzer in SQL Server 7.0 and 2000, with a schemata browser
- MySQL Administrator – Common administrative tasks such as creating, altering, and dropping tables in a database can be performed visually via the Table Editor. Indexes and constraints such as foreign keys can also be defined here.
- MySQL System Tray Monitor - Similar to the Service Manager in SQL Server 2000, this tool puts an icon in the Windows SysTray to display the status of the MySQL Instance.
How to change image with onclick?
To change the image using OnClick function i have found 2 ways.
1. Using jQuery.
2. Normal JavaScript.
Lets look one by one.
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> <script type="text/javascript"> $(document).ready(function(){ $("#ChangeImage").click(function(){ $('#ChangeImage').attr('src','yahoo.gif'); }); }); </script> <img src="bm_yahoo.gif" name="my_pic" id="ChangeImage"> |
second by using simple JavaScript. I suggest not you use direct JavaScript call function. Good PHP Technology companies are not using like this.
<script type="text/javascript"> function changePic() { document.getElementById("Img1").src="bm_yahoo.gif"; } </script> <a href="#" onclick="changePic()";><img border="0" id="Img1" src="yahoo.gif" /></a> </script> |
