ns-1m
commented
12 years ago This is the function,
else if(type == SQLITE_BLOB){
//NSLog(@"blob");
NSData *aData = [[NSData alloc]dataWithBytes:sqlite3_column_blob(statement, colNum) length:sqlite3_column_bytes(statement,colNum)];
[row addObject:aData];
[aData autorelease];
}
else{//SQLITE_NULL
//NSLog(@"column type: %d",type);
[row addObject:@"null"];
}
coomsie
ecanas
marcucio
It seems that null values are either not being saved or returned properly. Instead of saving a null value in a field I get 0 or '' depending on the datatype.
Below is code from QuickConnect which has a native client, maybe you can use some of the code, I noticed they have a blob section which you can use on your code and they have a function called "sqlite3_bind_null" not sure what it's doing exactly but could fix the null value problem.
/* Copyright (c) 2008, 2009 Lee Barney Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
The end-user documentation included with the redistribution, if any, must include the following acknowledgment: "This product was created using the QuickConnect framework. http://www.quickconnectfamily.org", in the same place and form as other third-party acknowledgments. Alternately, this acknowledgment may appear in the software itself, in the same form and location as other such third-party acknowledgments.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
import "SQLiteDataAccess.h"
import "QCParameter.h"
import
static NSString *dbSemaphore = @"dblock";
// Private interface for AppDelegate - internal only methods. @interface SQLiteDataAccess (Private)
@end
@implementation SQLiteDataAccess
(SQLiteDataAccess)initWithDatabase: (NSString) dbName isWriteable: (BOOL) isWriteable{ //if (self = [super init]) { NSString *path = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:dbName]; if(isWriteable){
} sqlite3 *aDatabase; //NSLog(@"path: %@",path); if (sqlite3_open([path UTF8String], &aDatabase) == SQLITE_OK) { //NSLog(@"database opened"); self->database = aDatabase;
} else{ //since we failed to open the database completely close it down to make sure that everyting is cleaned up sqlite3_close(aDatabase); NSAssert1(0, @"Failed to open database with message '%s'.", sqlite3_errmsg(aDatabase)); } //} return nil; }
(DataAccessResult)dbAccess:(NSString)SQL withParameters:(NSArray_)parameters treatAsChangeData:(BOOL)treatAsChangeData{ SQL = [SQL stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; //NSLog(@"paramArrayString after 1: %@\n\n\n",SQL); //NSLog(@"in dbAccess"); DataAccessResult theResult; //what is being returned theResult = [DataAccessResult alloc]; if(parameters != nil && [parameters count] > 0){ //make sure the the number of parameters is equal to the number of qestion marks in the SQL string } int numResultColumns = 0; sqlite3_stmt statement = nil; // Preparing a statement compiles the SQL query into a byte-code program in the SQLite library. // The third parameter is either the length of the SQL string or -1 to read up to the first null terminator. const char_ SQLChar = [SQL UTF8String];//this needs to be deallocated after we don't need it any more. //NSLog(@"about to prepare %@",SQL); if (sqlite3_prepare_v2(database, SQLChar, -1, &statement, NULL) == SQLITE_OK) { if(!treatAsChangeData){ //NSLog(@"columns not changing"); //retrieve the number of columns in the result of the execution of the select statement numResultColumns = sqlite3_column_count(statement); //NSLog(@"numRecentColumns: %i",numResultColumns); NSAutoreleasePool pool = [[NSAutoreleasePool alloc] init]; NSMutableArray fieldNames = [[NSMutableArray alloc] initWithCapacity:0]; for(int i = 0; i < numResultColumns; i++){ const char name = sqlite3_column_name(statement, i); NSString \ columnName = [[NSString alloc]initWithCString:name encoding:NSUTF8StringEncoding]; [fieldNames addObject:columnName]; [columnName autorelease]; } [theResult setFieldNames:fieldNames]; [fieldNames autorelease];
} else{ /NSString error; error = [[NSString alloc]initWithCString:sqlite3_errmsg(database) encoding:NSASCIIStringEncoding]; [theResult setErrorDescription:error]; [error release]; */ [theResult setErrorDescription:[NSString stringWithUTF8String:sqlite3_errmsg(database)]];
} // "Finalize" the statement - releases the resources associated with the statement. sqlite3_finalize(statement); //[pool drain]; //NSLog(@"returning: %@",theResult); return theResult; }
}
// internal bind methods
(int) bind_blob:(sqlite3stmt)statement withIndex:(int)parameterIndex andBindVariable:(NSData_)aVariable{
if (![aVariable respondsToSelector:@selector(lengthOfBytes:)]) { return -1; } //by default have the library make a copy, SQLITE_TRANSIENT, since we don't know if the variable may be changed //by something else in the application. return sqlite3_bind_blob(statement, parameterIndex, aVariable, [aVariable length], SQLITE_TRANSIENT); }
@end