Read chinese characters from SQLite...

[zaz]

Hello all,

I am working on an app that has to read Chinese words from an SQLite database. Initially I used a pretty basic way of retrieving the data from the db:

sqlite3 *Database(void)
{
	//NSString *cards;
	NSString *file = [[NSBundle mainBundle] pathForResource:@"chinese" ofType:@"db"];
	if(sqlite3_open([file UTF8String], &database) == SQLITE_OK)
	{
		if(sqlite3_exec(database, "select chinTraditional from words where chap = '1'", dbCallBack, cards, NULL))
		{
			NSLog(@"Success");
		}
		else
			NSLog(@"Q Fail");
	
	return database;
}

where dbCallBack is :

int dbCallBack(void *na, int argc, char **argv, char **colName)
{
      for(int i = 0; i < argc; i++)
      {
		NSLog([NSString stringWithFormat:@"Chinese = %C\n", argv[i] ? argv[i] : "NULL"]);
	}
	return 0;
}

I wanted to display the current Chinese word with NSLog, but I get wrong values.

I thought that the problem might be in argv being an array of chars, which are of smaller size than the one needed for unicode. I tried other using sqlite3_prepare_v2 instead and statements instead of this method but I was not sure how to proceed and whether this could get me out of the problem.

Could anyone lend me a hand, or give me a hint in how to proceed with the task of reading the Chinese characters from the database and assigning them to a variable that I can use elsewhere in the code?

Thanks a lot!

I have been looking for solutions for the past 3-4 hours and I could find anything that fixes my problem.

[dljeffery]

%C is definitely not correct in your NSLog statement. That would be for a unicode character; you are dealing with strings, not characters, so you want %S here. Although I'm not sure you can accomplish what you want by using that callback function required by sqlite3_exec.

I would try replacing your sqlite3_exec call with separate calls to sqlite3_prepare_v2 and sqlite3_step. And then look at sqlite3_column_text16 to get your unicode strings after each step call.

SQLite definitely supports what you are trying to do... I'm not using it directly; I'm going through Core Data, but I am having no problems storing and retrieving Kanji.

[zaz]

Thanks dljeffery, I wrote this line while typing my post, and I didn't pay too much attention.

I did as you said. It is certainly worth it to know what is behind the SQLite wrapper functions.

It turned out that my problem was in the database that I was using. I converted it to SQLite from MySQL using a database manager (SQLite2009 pro) which is available for free. I couldn't get this software to work for unicode characters, as it just stores what the unicode characters from the original database would look in ASCII (e``^&* stuff) in the SQLite one. I tried converting these values to UTF-8 in xcode but I couldn't.

Do you usually convert ASCII to UTF8 by using stringWithUTF8String?

[chopgood]

the following code worked for me with correct character encoding and display,

// Loop columns of returned record
for (int i=0; i < nColumns; i++) {
    NSString *value = [NSString stringWithUTF8String:(char *)sqlite3_column_text(stmt, i)];  
    NSLog(@"%@",value);              
}