I asked over on the SQLite mailing list about whether they could add a built-in function to SQLite to reverse a character string. I know how to do this in ActionScript in the client but I have good reasons for wanting the function in the database. Sometimes I might want to do this when working at the SQLite3.exe command-line. But I wanted to have the reversal occur in the database mainly because the original string could contain decomposed Unicode sequences; I wanted to avoid completely any possibility of the Adobe libraries or any other library raising a "malformed Unicode character" error if they should encounter the codepoint for a combining form before encountering the codepoint for the base-character, as could occur when the codepoints are flipped "raw" without regard for preserving composed sequences.
Oracle has a reverse function in its "raw" libraries and SQLServer has a reverse function that reverses the order of characters in a string codepoint-by-codepoint, so I am hoping the folks at SQLite have been convinced to add it, but who knows.
Anyway, enough background. Here's the question. I kept getting the advice to "write my own C function to do the reversal" and simply have "my application register the C function with SQlite". Do the Adobe libraries for SQLite support custom user function registration?
Here is the link to the updated documentation, not all of which I understand. I hope the SQLite folks at Adobe could provide an answer.
http://www.sqlite.org/cvstrac/wiki?p=LoadableExtensions
Thanks
