sql - 将两个表与表 2 的数据从第二个字段开始合并

Question

我有两个表，每个表有 72 列。第一个表的数据从第 1 列开始，第二个表的数据从第 30 列开始。如何在两个表上进行联合并在第二个表值的前 29 列中获取 0？

Answer 1

为此，您必须明确写入 29 列，默认值为 0（零）。

对于表 B 中存在的列的表 A 选择，您也必须这样做。

假设表 B 有 20 列名为 col30,col31,col32 ....... col49

您可以使用以下查询 -

select TableA. col1,
       TableA. col2,
       TableA. col3,
       TableA. col4,
       TableA. col5,
       TableA. col6,
       TableA. col7,
       TableA. col8,
       TableA. col9,
       TableA. col10,
       TableA. col11,
       TableA. col12,
       TableA. col13,
       TableA. col14,
       TableA. col15,
       TableA. col16,
       TableA. col17,
       TableA. col18,
       TableA. col19,
       TableA. col20,
       TableA. col21,
       TableA. col22,
       TableA. col23,
       TableA. col24,
       TableA. col25,
       TableA. col26,
       TableA. col27,
       TableA. col28,
       TableA. col29,
       0       col30,
       0       col31,
       0       col32,
       0       col33,
       0       col34,
       0       col35,
       0       col36,
       0       col37,
       0       col38,
       0       col39,
       0       col40,
       0       col41,
       0       col42,
       0       col43,
       0       col44,
       0       col45,
       0       col46,
       0       col47,
       0       col48,
       0       col49,
       0       col50
  from tableA

union all

select 0       col1,
       0       col2,
       0       col3,
       0       col4,
       0       col5,
       0       col6,
       0       col7,
       0       col8,
       0       col9,
       0       col10,
       0       col11,
       0       col12,
       0       col13,
       0       col14,
       0       col15,
       0       col16,
       0       col17,
       0       col18,
       0       col19,
       0       col20,
       0       col21,
       0       col22,
       0       col23,
       0       col24,
       0       col25,
       0       col26,
       0       col27,
       0       col28,
       0       col29,
       TableB. col30,
       TableB. col31,
       TableB. col32,
       TableB. col33,
       TableB. col34,
       TableB. col35,
       TableB. col36,
       TableB. col37,
       TableB. col38,
       TableB. col39,
       TableB. col40,
       TableB. col41,
       TableB. col42,
       TableB. col43,
       TableB. col44,
       TableB. col45,
       TableB. col46,
       TableB. col47,
       TableB. col48,
       TableB. col49,
       TableB. col50
  from TableB