//
//  CCSqlite3.h
//  CCFC
//
//


#import <Foundation/Foundation.h>
#import <sqlite3.h>


@class CCSqlite3;




@protocol CCSqlite3Delegate


// the row starts with 1.
- (void)onCCSqlite3AnotherRowOK:(CCSqlite3 *)sqlite withRow:(int)row;


@end






@interface CCSqlite3 : NSObject 
{
@private
        sqlite3                                 *_db;
        
        NSString                                *_sql;
        sqlite3_stmt                    *_statement;
        
        id<CCSqlite3Delegate>   _delegate;
        int                                             _row;
}


@property(nonatomic, assign)                    id                              delegate;


// if you don't want to call getData method, then get the statement by yourself.
@property(nonatomic, assign, readonly)  sqlite3_stmt    *statement;


- (id)initWithSqliteDBFullPath:(NSString *)dbFullPath;
- (void)dealloc;


- (void)setSql:(NSString *)sql;


- (BOOL)prepare;
- (void)getData;


- (void)end;


// set so, we can get the random results
- (void)setRandomReturns:(int)n;


// if set so, the sqlite will returns the rowCount row data, which starts from argument start.
- (void)setNRowsFrom:(int)start withRowCount:(int)rowCount;




@end

//
//  CCSqlite3.m
//  CCFC
//
//


#import "CCSqlite3.h"




@implementation CCSqlite3


@synthesize delegate = _delegate;
@synthesize statement = _statement;


- (id)initWithSqliteDBFullPath:(NSString *)dbFullPath
{
        self = [super init];
        int ret;
        if(self)
        {
                ret = sqlite3_open([dbFullPath UTF8String], &_db);
                if(ret != SQLITE_OK)
                        return nil;
        }
        return self;
}


- (void)dealloc
{
        [_sql release];
        sqlite3_close(_db);
        [super dealloc];
}


- (void)setSql:(NSString *)sql
{
        if(_sql != sql)
        {
                [_sql release];
                _sql = [sql copy];
        }
}


- (BOOL)prepare
{
        return (sqlite3_prepare_v2(_db, [_sql UTF8String], -1, &_statement, NULL) == SQLITE_OK);
}


- (void)getData
{
        while (sqlite3_step(_statement) == SQLITE_ROW)
        {
                ++_row;
                [_delegate onCCSqlite3AnotherRowOK:self withRow:_row];
        }
}


- (void)end
{
        sqlite3_finalize(_statement);
}


// set so, we can get the random results
- (void)setRandomReturns:(int)n
{
        NSString *temp = [NSString stringWithFormat:@" order by random() limit %d", n];
        NSString *final = [_sql stringByAppendingString:temp];
        [self setSql:final];
}


// if set so, the sqlite will returns the rowCount row data, which starts from argument start.
- (void)setNRowsFrom:(int)start withRowCount:(int)rowCount
{
        NSString *temp = [NSString stringWithFormat:@" limit %d,%d", start, rowCount];
        NSString *final = [_sql stringByAppendingString:temp];
        [self setSql:final];
}


@end

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