sql - 在 SQL 中将一行拆分为两部分的问题

Question

我想将一行分成两部分，我使用的是 UNION ALL。我得到了这两个部分，但结果不是我想要的。顺序乱了 我想要#3 和#4 行开关，以及#7 和#8 行开关位置。

原始行：

TIME, ORDER_NUM, THICKNESS, FORMULATION, SILO, SCREWOIL1_TEMP, SCREWOIL2_TEMP, MELTING_TEMP, FEEDER_LB, FEEDER_RPM, COMPOUND, RECLAIM_PERCENTAGE

所需的顺序应该是：

第一排：

TIME, ORDER_NUM, THICKNESS, FORMULATION, SILO, SCREWOIL1_TEMP, SCREWOIL2_TEMP

第二行：

TIME, MELTING_TEMP, FEEDER_LB, FEEDER_RPM, COMPOUND, RECLAIM_PERCENTAGE

标签： sql

Answer 1

如果要交错记录，则需要额外的排序键。

select TIME, ORDER_NUM, THICKNESS, FORMULATION, SILO, SCREWOIL1_TEMP, SCREWOIL2_TEMP, MELTING_TEMP, FEEDER_LB, FEEDER_RPM, COMPOUND, RECLAIM_PERCENTAGE
from ((select TIME, ORDER_NUM, THICKNESS, FORMULATION, SILO, SCREWOIL1_TEMP, SCREWOIL2_TEMP, MELTING_TEMP, FEEDER_LB, FEEDER_RPM, COMPOUND, RECLAIM_PERCENTAGE,
              1 as priority
       from . . .
      ) union all
      (select TIME, MELTING_TEMP, FEEDER_LB, FEEDER_RPM, COMPOUND, RECLAIM_PERCENTAGE,
              2
       from . . .
      )
     ) t
order by time, priority;

请注意，列标题均取自union all. 结果集中的所有行都具有相同的列名。