PLSQL 变量

Question

我是编程新手，我想知道如何声明一个可以在我的代码中使用的变量。

我想要实现的是：

Myvariable = (select Column from table1 where column =1234 group by column);
select column from table2 where column in (myvariable);
select column from table3 where column in (myvariable);

等等

提前致谢:)

Answer 1

这不是一个真正的变量...你可以这样写 sql

select column 
from table2 
where column in (select Column from table1 where column =1234 group by column);

Answer 2

如果您使用 PL/SQL Developer 访问 Oracle 数据库，您可以使用类似于以下的代码创建测试 window（文件 - 新建 - 测试 Window）：

DECLARE
  myVariable  TABLE1.COLUMN%TYPE := 1234;
BEGIN
  FOR aRow2 IN (SELECT COLUMN
                  FROM TABLE2
                  WHERE COLUMN = myVariable)
  LOOP
    DBMS_OUPUT.PUT_LINE('Do something with ''aRow2''');
  END LOOP;

  COMMIT;

  FOR aRow3 IN (SELECT COLUMN
                  FROM TABLE3
                  WHERE COLUMN = myVariable)
  LOOP
    DBMS_OUPUT.PUT_LINE('Do something with ''aRow3''');
  END LOOP;

  COMMIT;
END;

您需要编辑以上内容以对 TABLE2 和 TABLE3 中的行执行任何操作。

祝你好运。

Answer 3

您可以使用绑定到当前会话的临时 TEMPORARY TABLE：

DECLARE GLOBAL TEMPORARY TABLE temp
{ 
    column INTEGER 
}
ON COMMIT DELETE ROWS  -- Specify PRESERVE ROWS if you want to keep them through commits
NOT LOGGED 
ON ROLLBACK DELETE ROWS  -- Remove this line if you want to keep rows when  you rollback a transaction

您加载 table:

insert into temp1 (select Column from table1 where column =1234 group by column)

然后您可以使用通用代码使用数据：

select column from table2 where column in (select column from temp1);
select column from table3 where column in (select column from temp1);

PLSQL 变量

PLSQL Variables

sql

variables

subquery

declare

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