OC本地数据分页读取

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主要是sql语句limit的使用

PS:

原来做的项目涉及到分页都是后台处理的。但是最近有个项目需要自己本地做分页。于是自己尝试着写了一下主要还是sql语句limit的使用 废话不多说，直接上代码吧

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+ (NSMutableArray *)getAllMessage:(NSString *)type page:(NSString *)page size:(NSString *)size{

    
    FMDatabase *db = [SendIFDataBaseUnity getDatabase];
    
    if (![db open]) {
        return nil;
    }
    [db setShouldCacheStatements:YES];
    if (![db tableExists:@"messagetable"]) {
        
        return nil;
    }
    int limit0;
    int limit1;
    
    if ([page intValue] == 0) {
        
        limit0 = 0;
        limit1 = 9;
        
    }else{
    
        limit0 = [page intValue]*[size intValue];
        limit1 = [page intValue]*[size intValue]+9;
    }

    NSString *sql;
    if ([type intValue] == -1) { //全部
       

           sql = [NSString stringWithFormat:@"select * from messagetable  order by createTime desc limit 10 offset %d",limit0];
    }else{
    
            sql = [NSString stringWithFormat:@"select * from messagetable where type=%@ order by createTime desc limit %d,%d",type,limit0,limit1];
    }

    
    FMResultSet *resultSet = [db executeQuery:sql];
    NSMutableArray *resultArr = [[NSMutableArray alloc] initWithCapacity:0];
    
    
    while ([resultSet next]) {

        //这里处理模型赋值    
    }
    
    [resultSet close];
    [db close];
    return resultArr;
}