Question

I have 6MB memory leaks when I’m working with sqlite. Now I’m testing getBookWithIdTest method.

-(IBAction) onTest:(id)sender
{
 NSAutoreleasePool *myPool = [[NSAutoreleasePool alloc] init];
 for (int i=0; i<100; i++) 
 {
    [DatabaseManager getBookWithIdTest:i];
 }
 [myPool drain];    
} 

I have 6 MB leaked memory. But why?

+ (BookSettings *)getBookWithIdTest:(int)abookId
{
  BookSettings *book = [[[BookSettings alloc] init] autorelease];    
  sqlite3 *database;

  if(sqlite3_open([DatabaseManager databasePath], &database) == SQLITE_OK) 
  {
    sqlite3_stmt *compiledStatement;

    //FIRST PART
    const char *sqlStatementBook = [[NSString stringWithFormat:@"SELECT * FROM t_abooks"] cStringUsingEncoding:NSASCIIStringEncoding];

    if(sqlite3_prepare_v2(database, sqlStatementBook, -1, &compiledStatement, NULL) == SQLITE_OK)
    {            
        while(sqlite3_step(compiledStatement) == SQLITE_ROW) 
        {               
        }             
    } 
    else NSLog(@"sqlite3_prepare_v2 error %s", sqlite3_errmsg(database));

    sqlite3_reset(compiledStatement);
   //END FIRST PART
    // SECOND PART
    const char *sqlStatementAuthors = [[NSString stringWithFormat:@"SELECT * FROM t_authors"] cStringUsingEncoding:NSASCIIStringEncoding];

    if(sqlite3_prepare_v2(database, sqlStatementAuthors, -1, &compiledStatement, NULL) == SQLITE_OK)
    {
        while(sqlite3_step(compiledStatement) == SQLITE_ROW) 
        {                
        }            
    } 
    else NSLog(@"sqlite3_prepare_v2 error %s", sqlite3_errmsg(database));

    sqlite3_reset(compiledStatement);
    //END SECOND PART
    sqlite3_finalize(compiledStatement);
} else NSLog(@"sqlite3_open error");

sqlite3_close(database);
return book;
}  

But If I removed FIRST PART or SECOND PART I’ll have no leaks.
For example

+ (BookSettings *)getBookWithIdTest:(int)abookId
{
BookSettings *book = [[[BookSettings alloc] init] autorelease];    
sqlite3 *database;

if(sqlite3_open([DatabaseManager databasePath], &database) == SQLITE_OK) 
{
    sqlite3_stmt *compiledStatement;

    //FIRST PART -removed        
    // SECOND PART
    const char *sqlStatementAuthors = [[NSString stringWithFormat:@"SELECT * FROM t_authors"] cStringUsingEncoding:NSASCIIStringEncoding];

    if(sqlite3_prepare_v2(database, sqlStatementAuthors, -1, &compiledStatement, NULL) == SQLITE_OK)
    {
        while(sqlite3_step(compiledStatement) == SQLITE_ROW) 
        {                
        }            
    } 
    else NSLog(@"sqlite3_prepare_v2 error %s", sqlite3_errmsg(database));

    sqlite3_reset(compiledStatement);

    sqlite3_finalize(compiledStatement);
} else NSLog(@"sqlite3_open error");

sqlite3_close(database);
return book;
}

Answer 1

I solved the problem. I need to add

sqlite3_finalize(compiledStatement);

to the END of FIRST PART.