php - 在单个MySQL查询中使用多个临时表（适用于phpMyAdmin，但不适用于PHP）

我想避免使用真实表作为解决方法。我正在尝试连接两个表并为我正在调用unique_values_needed的列获取唯一值，同时在重复real_secondary_table_primary_key时存在值11的优先级。

这是代码（它在phpMyAdmin中运行，但不在PHP中运行）：

CREATE TEMPORARY TABLE IF NOT EXISTS temporary_table_1
    AS (SELECT real_main_table.*, 
               real_secondary_table.real_secondary_table_primary_key 
          FROM real_main_table
               LEFT JOIN real_secondary_table 
                         ON real_secondary_table.real_main_table_primary_key = real_main_table.real_main_table_primary_key
      ORDER BY real_main_table.date DESC);

CREATE TEMPORARY TABLE IF NOT EXISTS temporary_table_2
    AS (SELECT real_main_table.*, 
               real_secondary_table.real_secondary_table_primary_key 
          FROM real_main_table
               LEFT JOIN real_secondary_table 
                         ON real_secondary_table.real_main_table_primary_key = real_main_table.real_main_table_primary_key
      ORDER BY real_main_table.date DESC);

UPDATE temporary_table_1 t1, temporary_table_2 t2
   SET t1.real_secondary_table_primary_key = t2.real_secondary_table_primary_key
 WHERE     t1.real_main_table_primary_key = t2.real_main_table_primary_key 
       AND t1.real_secondary_table_primary_key  11 
       AND t2.real_secondary_table_primary_key = 11;

  SELECT * 
    FROM temporary_table_1 
GROUP BY unique_values_needed
ORDER BY temporary_table_1.date DESC;

我也尝试了以下内容（同样，它在phpMyAdmin中运行，但仍然不在PHP中）：

CREATE TEMPORARY TABLE IF NOT EXISTS temporary_table_1
    AS (SELECT real_main_table.*, 
               real_secondary_table.real_secondary_table_primary_key 
          FROM real_main_table
               LEFT JOIN real_secondary_table 
                         ON real_secondary_table.real_main_table_primary_key = real_main_table.real_main_table_primary_key
      ORDER BY real_main_table.date DESC);

UPDATE temporary_table_1 t1, (
       SELECT real_main_table.*, 
              real_secondary_table.real_secondary_table_primary_key 
         FROM real_main_table
              LEFT JOIN real_secondary_table 
                        ON real_secondary_table.real_main_table_primary_key = real_main_table.real_main_table_primary_key
     ORDER BY real_main_table.date DESC) t2
   SET t1.real_secondary_table_primary_key = t2.real_secondary_table_primary_key
 WHERE     t1.real_main_table_primary_key = t2.real_main_table_primary_key 
       AND t1.real_secondary_table_primary_key  11 
       AND t2.real_secondary_table_primary_key = 11;

  SELECT * 
    FROM temporary_table_1 
GROUP BY unique_values_needed
ORDER BY temporary_table_1.date DESC;

当我使用mysql_query($query) or die(mysql_error())进行检查时，错误应该是在创建第二个临时表（在第一个代码示例中）时，或者在使用UPDATE时在(SELECT ...) t2中（在第二个代码示例）。

在单个MySQL查询中使用多个临时表（适用于phpMyAdmin，但不适用于PHP）

1 个答案: