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How to add ntfs support to mac

August 7th, 2012 No comments

This is a very short flow to follow. First you need to install “Macfuse”. You can get this small application from this link: http://code.google.com/p/macfuse/  . This application allows you to extend Mac OS X’s native file handling capabilities via 3rd-party file systems. It is used as a software building block by dozens of products. Then, one last step left. Now you can start with installing Fuse-ext2. This is an extension to macfuse, so the macfuse is required to install beforehand. Fuse-ext2 is a multi OS FUSE module to mount ext2 and ext3 file system devices and/or images with read write support.

fuse-ext2 macfuse

fuse-ext2 macfuse

If you installed these applications successfully, now you should be able to read/write ntfs and fat formatted disks through your mac

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Categories: MacOS, Tips Tags:

Manage your virtual hosts on apache server easily

May 28th, 2011 No comments

Building up and making all modifications on your server is pretty boring. There is no need to find the sun again and again. I’ve had to go through the process of reconfiguring my virtual hosts for Apache2 several times and i found a pre modified shell script and modified the script according to my needs. This script enables you to create, destroy your virtual host in a second.

you can download the script from here : vhost.txt or;

mkdir ~/bin
cd ~/bin
wget http://samet.kilictas.com/wp-content/uploads/2011/05/vhost.txt
mv vhost.txt vhost
chmod 755 vhost

Now, to invoke the script, type the following:

. ~/bin/vhost

By using this script you can create, destroy a virtual host. In order to create a new host on your server user following command by replacing appreciate values:

vhost create <domain> <admin -email> <host -ip>

The script creates required directories,files as shown below;

Web directories
/www/htdocs/$domain

Web cgi-bin
/www/cgi-bin/$domain

Web logs
/www/logs/$domain/apache2
/www/logs/$domain/apache2/access.log
/www/logs/$domain/apache2/error.log

then builds virtual host config file and enables it right away (enabling is optional), which is placed in following directory

/etc/apache2/sites-available/$domain

After getting done with all these process it simply creates a little info file

/www/$domain/logs/site_info

Great you have created and enabled your virtual host, you may need to destroy a virtual host, here is how;

vhost destroy <domain>

Read more…

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Categories: General, HowTo, Linux, Tips Tags: , ,

if exists syntax in sybase

April 20th, 2010 1 comment

Below shows the if exists usage with examples in sybase

If exists (select record)
begin
sql statement 1
sql statement 2
end
else
begin
sql statement 3
sql statement 4
end

Example

Scripts that include constructs like the following may produce errors if the table described in the script does not include the specified column:

if exists (select 1 from syscolumns
where id = object_id("some_table")
and name = "some_column")
begin
alter table some_table drop some_column
end

In this example, some_column must exist in some_table for the batch to succeed.

If some_column exists in some_table, the first time you run the batch, alter table drops the column. On subsequent executions, the batch does not compile.

Adaptive Server raises these errors while preprocessing this batch, which are similar to those that are raised when a normal select tries to access a nonexistent column. These errors are raised when you modify a table’s schema using clauses that require a data copy. If you add a null column, and use the above construct, Adaptive Server does not raise these errors.

To avoid such errors when you modify a table’s schema, include alter table in an execute immediate command:

if exists (select 1 from syscolumns
where id = object_id("some_table")
and name = "some_column")
begin
exec ("alter table some_table drop
some_column")
end

Because the execute immediate statement is run only if the if exists() function succeeds, Adaptive Server does not raise any errors when it compiles this script.

You must also use the execute immediate construct for other uses of alter table, for example, to change the locking scheme, and for any other cases when the command does not require data copy.

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A common error with GROUP BY Clause

April 16th, 2010 No comments

A common error with groups is to try to get information which cannot properly be put in a group. For example,


SELECT sales_rep, emp_lname, count( * )
FROM sales_order
KEY JOIN employee
GROUP BY sales_rep

gives the error

column ‘emp_lname’ cannot be used unless it is in a GROUP BY.

SQL does not realize that each of the rows for an employee with a given ID have the same value of emp_lname. An error is reported since SQL does not know which of the names to display.

However, the following is valid:


SELECT sales_rep, max( emp_lname ), count( * )
FROM sales_order
KEY JOIN employee
GROUP BY sales_rep

The max function chooses the maximum (last alphabetically) surname from the detail rows for each group. The surname is the same on every detail row within a group so the max is just a trick to bypass a limitation of SQL.

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Categories: SQL, Tips Tags: , , , , , , ,

How to enable TCP connections to XServer?

December 7th, 2009 No comments

sudo gedit /etc/gdm/gdm.schemas

find:

<schema>
<key>security/DisallowTCP</key>
<signature>b</signature>
<default>true</default>
</schema>

shift from true to false:

<schema>
<key>security/DisallowTCP</key>
<signature>b</signature>
<default>false</default>
</schema>

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Categories: Linux, Tips, Ubuntu Tags: , ,