小编Bas*_*ast的帖子

我的目标是合并两个不同的阵列.

我有表"a"和"b".表"a"中的数据更优先.

问题:如果来自"a"的键包含空值,我想从表"b"中取出一个.

这是我的代码:

<?php

$a = array('key1'=> "key1 from prioritar", 'my_problem'=> "");

$b = array('key1'=> "key1 from LESS prioritar", 'key2'=>"key2 from LESS prioritar", 'my_problem'=> "I REACHED MY GOAL!");

$merge = array_merge($b, $a);

var_dump($merge);

有没有办法在一个函数中执行此操作而不执行下面的操作？

foreach($b as $key => $value)
{
  if(!array_key_exists($key, $a) || empty($a[$key]) ) {
    $a[$key] = $value;
  }
}

当我们使用InnoDB表在MySQL中进行“ SELECT FOR UPDATE”时，有什么方法可以跳过“锁定行”吗？

例如：终端t1

mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)

mysql> select id from mytable ORDER BY id ASC limit 5 for update;
+-------+
| id    |
+-------+
|     1 |
|    15 |
| 30217 |
| 30218 |
| 30643 |
+-------+
5 rows in set (0.00 sec)

mysql> 

同时，终端t2：

mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)

mysql> select id from mytable where id>30643 order by id asc limit 2 …

有没有办法通过一个巨大的数据库并并行应用一些工作来获取条目？我尝试使用 ExecutorService，但我们必须关闭（）才能知道池大小......

所以我最好的解决方案是：

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

public class TestCode
{
private static List<String> getIds(int dbOffset, int nbOfArticlesPerRequest) 
{
    return Arrays.asList("1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", "25", "26", "27", "28", "29");
}

public static void main(String args[]) throws Exception
{
    int dbOffset = 0;
    int nbOfArticlesPerRequest = 100;
    int MYTHREADS = 10;
    int loopIndex = 0;
    boolean bContinue=true; …