query select Sqlite Objective C iphone

well, I have problems with my queries,i dont know why!! please help

i try to select an id from a table named moneda and I give the name like parameter,

this is my method with my query :

-(int)ConsultaIdMoneda:(NSString*) nombreMonedaParametro
{
    int idMonedaObtenido;
    NSLog(@" entre a consultar id de la moneda desde el app delegate");
    sqlite3 *database;

    const char *path = [[[NSBundle mainBundle] pathForResource:@"database2" ofType:@"sqlite"] UTF8String];
    if(sqlite3_open(path, &database) == SQLITE_OK)      
    {
        const char *sqlStatement =[[NSString stringWithFormat:@"Select idMoneda from moneda Where nombre = %@",nombreMonedaParametro] cStringUsingEncoding:NSUTF8StringEncoding];

        NSLog(@"%s",sqlStatement);
        sqlite3_stmt *compiledStatement;
        NSInteger result = sqlite3_prepare_v2(database,sqlStatement, -1, &compiledStatement, NULL);
        NSLog(@"%s",sqlStatement);
        if(result == SQLITE_OK) 
        {
            idMonedaObtenido = [[NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 0)] intValue];
        }
        else
        {
            NSAssert1(0, @"Error . '%s'", sqlite3_errmsg(database));            
        }
        sqlite3_reset(compiledStatement);
        sqlite3_finalize(compiledStatement);
    }

    sqlite3_close(database);
    return idMonedaObtenido;        
}

and this is the error:

2009-12-03 00:28:45.715 BCDTravel[1220:20b] *** Assertion failure in -[BCDTravelAppDelegate ConsultaIdMoneda:], /Users/Mely/Desktop/BCDTravel version 45/Bcd/Classes/BCDTravelAppDelegate.m:101
2009-12-03 00:28:45.717 BCDTravel[1220:20b] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Error haciendo el select. 'no such column: euros''

i think the problem is in this line but i dont know how to slove sugge开发者_运维问答stions pleasee!!

const char *sqlStatement =[[NSString stringWithFormat:@"Select idMoneda from moneda Where nombre = %@",nombreMonedaParametro] cStringUsingEncoding:NSUTF8StringEncoding];

Because you are passing a character value you need to put quotes around the parameter in the SQL.

For example:

SELECT idMoneda
FROM   moneda
WHERE  nombre = '%@'

Otherwise, when the SQL is compiled, the value you pass in is itself treated as a column name (euros) instead of a candidate value of the nombre column.

Suggest you look into using prepared statements rather than assembling the string 'manually'. See this related SO question.

If you have special characters in select query, Use NSUTF8StringEncoding instead of NSASCIIStringEncoding.

NSString *s = @"select * from AddressGeocode where address like 'São Paulo, Brazil'";

const char *sqlStatement = [s cStringUsingEncoding:NSUTF8StringEncoding];