Blogs

A database user asks:

Should I use Dropbox as a virtual server for database files?

Answer:

The mechanics of Dropbox do not lend to simultaneous editing, which is the nature of most database files. Don't attempt to run, or sanction running a database file from a shared folder, Dropbox folders included.

Basically, Dropbox works like this:

- I create a file, and upload it to Dropbox.
- I invite you to share the Dropbox folder
- Dropbox updates your Dropbox folder with my file.
- You edit the file from your Dropbox folder.
- Dropbox updates my Dropbox folder with your altered version of my file.

Since we're both working from our own local, downloaded copy of the Dropbox file, if we're both editing the file simultaneously, we're going to have a synchronization problem. Whose file gets precedence? User who attempt to share frequently edited files will have sync problems if they use Dropbox for collaborative files. Something like Google Docs would be a much better option for documents that will be edited by multiple users. Dropbox has a sole feasible purpose, which is keeping mostly static files synchronized across the web.

A FileMaker developer asks:

When developing a solution for sale to various clients who may require customization and/or integration with existing systems, is it better to offer them a single database with multiple tables, or multiple database files, each having its own unique functionality set?

Answer:

The more you develop databases, the more you'll discover that every business uses the same basic building blocks, or "bricks" as you say. Every business has customers. Every customer has employees. Every employee has contact info. Every business offers products or services. Every product or service has details and a price. Every business conducts transactions. Transactions often have multiple line items. Every business tracks events with dates and times, which can be represented in various views (calendar, task list, etc.). Build all of these basic blocks into your core files, and customize those core files for your current customer who tracks some non-standard data type.

Regarding space, empty database tables don't require much. More important, storage space is the cheapest hardware component you can get. A good developer will have an eye on efficiency and avoid adding lots of graphics, unnecessary fields and scripts, etc., which further serves to make storage concerns nearly moot. Much more valuable to your client is quick development time, and a solution that works without much modification. Multiple databases will not provide either. A single database with many tables and broad functionality will.

As to versatility/saleability, if you offer me a single, efficient file with lots of functionality I can use now and/or later, and the next guy plops a bulky set of 15-20 database files in front of me, my decision to buy your product is a very easy one. The latter will scare off any client, from the not-so-knowledgeable who may want the option to continue without your help at some point, to the somewhat knowledgeable client who will rightly view multiple database structure as an inferior design choice.

Apple's Activity Monitor is a good tool, especially for CPU and memory usage by application. However, when my disk starts running like crazy for no apparent reason, I often want to know why. Here are a couple of Terminal commands for monitoring disk activity:

sudo iotop -C 5 10

sudo fs_usage -f filesys

For explanations on how these tools work, and to access more options for each command, enter the following in Terminal:

man iotop

man fs_usage

A nice listing of Mac process names and descriptions:

http://triviaware.com/macprocess/all

To compress:

tar -zcvf archive_name.tar.gz folder_to_compress

To extract:

tar -zxvf archive_name.tar.gz

I've been using NetBeans 7 as my primary web programming IDE lately. I noticed a behavior that I thought was a bug: the blinking cursor kept disappearing... or so I thought. What was actually happening: the cursor's color was changing like a chameleon based on the text behind it. On a blank (white) line or tab, it was blinking white. When near text, it would blink black again, as one would expect from a normal caret.

The solution: Navigate to Options > Fonts & Colors > Highlighting > Caret Color, and change the Foreground color to a fixed color as opposed to Inherited. Using Inherited causes it to pick up the color of whatever is nearby, causing the illusion of a disappearing cursor.