Question

我需要比较不同数据库中类似表之间的行值。我如何知道哪些行不同。

e.g。 db1.foo (contains 2000 rows) and db2.foo (contains 2003 rows)。这两个表应该是相似的，我想知道如何找到应该是添加的行。注意：即使这些表中的主键ID也应该是相同的。

我无法访问任何GUI工具，并且想知道是否有任何SQL命令可用于执行此差异？

Answer 1

仅取决于对主键的检查：

    SELECT
        'a' AS DataOnlyInTable
      , a.*
    FROM
        db1.foo AS a
      LEFT JOIN 
        db2.foo AS b
          ON b.PK = a.PK
    WHERE b.PK IS NULL
UNION ALL 
    SELECT
        'b' AS DataOnlyInTable
      , b.*
    FROM
        db1.foo AS a
      RIGHT JOIN 
        db2.foo AS b
          ON b.PK = a.PK
    WHERE a.PK IS NULL

根据对整行的检查：

    SELECT
        'a' AS DataOnlyInTable
      , a.*
    FROM
        db1.foo AS a
      LEFT JOIN 
        db2.foo AS b
          ON (b.PK, b.column2, b.column3, ...) 
           = (a.PK, a.column2, a.column3, ...)
    WHERE b.PK IS NULL
UNION ALL 
    SELECT
        'b' AS DataOnlyInTable
      , b.*
    FROM
        db1.foo AS a
      RIGHT JOIN 
        db2.foo AS b
          ON (b.PK, b.column2, b.column3, ...) 
           = (a.PK, a.column2, a.column3, ...)
    WHERE a.PK IS NULL

如何在表格中的行之间进行差异

1 个答案: