Open up FDS?
Adobe announced that it will open source the strip down version of LiveCycle Data Service called BlazeDS. From what I heard, BlazeDS provides AMF3 remoting without data management and its data push solution is not so scalable as LCDS. (features comparsion chart). The reason is that BlazeDB still uses the blocking [...]

Continue reading " Flex Remoting - AMF "

E4X is similar to XPath that is used to manipulate the structural xml in a scripting language. Here are some examples:
Delete node from XML
<root>
<level>
<detail></detail>
</level>
<level>
<detail></detail>
</level>
</root>
I want to make a copy of this XML (could be either of the three types of XML objects) and remove the <detail> nodes from every node no matter that hiarchy they [...]

Continue reading " Flex - Power of E4X "

Today, I have come across a technical issue that a process is taking too long to download a file from one of our file server. The reason is due to the number of the files of a folder is increased over time and finally reach to ~ 12000. If you use ftp, you need to [...]

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Query Processing Basic
Before tuning your slow query, you better understand how your database process your query first. Here are the steps:

Look up the query cache to see whether the resultset of your query is available. MySQL does this via hashing your query and use the hashed value to check for the results in the [...]

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Need of Indexes
Image of you have a table of user info, if the table contains 50 million of rows. Without index, running a query like below will need a full table scan. Clearly it is not efficient as it is O(n) problem.
SELECT * FROM user_info WHERE last_name = “Tom”
But if we index it on [...]

Continue reading " Art of using database indexes "

Before you start tuning your server for mysql performance, you need to obtain the system information first. To do that, there are some linux command that may be useful.
top command

How to interpret the output from top command? Here you go.

The first line is telling you that the system is up 211 days 9 hr and [...]

Continue reading " Server Performance Tuning - MySQL "

Since I am leading the reporting team in Adconion, I would like to spend sometime on the new component “Advanced Data Grid” from Flex 3. Being excited to know that this component has added many cool features on top of the DataGrid, I would like to find out whether it meets all my needs. Before [...]

Continue reading " Flex 3 - Advanced DataGrid "