1

我想在数据库表中插入 2000 行是否有任何方法可以非常快速地插入数据。当前我正在使用下面的代码在数据库中插入数据。

代码 ：-

+(NSString* )getDatabasePath{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"Crocodilian"];
    return writableDBPath;

}

+(NSMutableArray *)executeQuery:(NSString*)str{

    sqlite3_stmt *statement= nil;
    sqlite3 *database;
    NSString *strPath = [self getDatabasePath];
    NSMutableArray *allDataArray = [[NSMutableArray alloc] init];
    if (sqlite3_open([strPath UTF8String],&database) == SQLITE_OK) {
        if (sqlite3_prepare_v2(database, [str UTF8String], -1, &statement, NULL) == SQLITE_OK) {


            while (sqlite3_step(statement) == SQLITE_ROW) {
                            NSInteger i = 0;
                NSInteger iColumnCount = sqlite3_column_count(statement);
                NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
                while (i< iColumnCount) {
                    NSString *str = [self encodedString:(const unsigned char*)sqlite3_column_text(statement, i)];


                NSString *strFieldName = [self encodedString:(const unsigned char*)sqlite3_column_name(statement, i)];

                    [dict setObject:str forKey:strFieldName];
                    i++;
                }

                [allDataArray addObject:dict];
                [dict release];
            }
        }

        sqlite3_finalize(statement);
    } 
    sqlite3_close(database);
    return allDataArray;
}

提前致谢。

4

2 回答 2

2

您的问题是，您试图一次插入一行。SQLite 在每次插入后添加提交。我在插入大数据时遇到了类似的性能问题。我使用批量插入解决了它。

首先创建具有多个插入的查询（在这种情况下不需要准备好的语句）并立即触发查询。这有很大的性能改进。唯一的问题是，您必须在创建多个插入查询之前验证数据。

快乐编码..

于 2013-08-08T05:12:52.263 回答
2

您可以尝试像这样进行批量插入

我的表是Product(ProductID int,ProductName text,ShortDescription text)

sqlite3 *dtdb;
const char *dbpath=//database path

   if ((sqlite3_open(dbpath,&dtdb)==SQLITE_OK))
    {

        sqlite3_exec(dtdb, "BEGIN TRANSACTION", NULL, NULL, &errorMessage);


        char buffer[] = "INSERT INTO Product VALUES (?1, ?2, ?3)";

        sqlite3_stmt* stmt;
        sqlite3_prepare_v2(dtdb, buffer, strlen(buffer), &stmt, NULL);

        for (unsigned i = 0; i < array.count; i++)
        {
            NSDictionary *dict=[array objectAtIndex:i];

            NSArray *arKeys=[dict allKeys];


            sqlite3_bind_int(stmt,1, [[dict objectForKey:@"ProductID"]intValue]);
            sqlite3_bind_text(stmt, 2, [[NSString stringWithFormat:@"%@",[dict objectForKey:@"ProductName"]]UTF8String], -1, SQLITE_STATIC);
            sqlite3_bind_text(stmt, 3, [[NSString stringWithFormat:@"%@",[dict objectForKey:@"ShortDescription"]]UTF8String], -1, SQLITE_STATIC);


            if (sqlite3_step(stmt) != SQLITE_DONE)
            {
                printf("Commit Failed!\n");
            }

            sqlite3_reset(stmt);
        }
        if(sqlite3_exec(dtdb, "COMMIT TRANSACTION", NULL, NULL, &errorMessage)==SQLITE_OK)
        {
            NSLog(@"commited products all");
        }
        else
        {
            NSLog(@"commited  fail products all");
        }
        sqlite3_finalize(stmt);

    }

    sqlite3_close(dtdb);
于 2013-08-08T05:23:43.797 回答