遍历表列的列表，并对它们应用查询 [英] Loop through a list of table columns, and apply a query to them

问题描述

我们有mytable表，其中包含列:id，值，描述....

We have our table mytable, that contains columns: id, value, description....

现在，我想将此SQL查询应用于每列:

Now I want to apply this sql query to each column:

select distinct [column] from mytable; 

有没有办法做到这一点?

Is there a way to do this?

nb.我想提供要遍历的列列表，而不是遍历表中的每一列.

nb. I want to provide the list of columns to loop through, rather than looping through every column in the table.

推荐答案

declare
  l_tab_name varchar2(32) := 'MY_TABLE';
begin
  for c1 in (select t.column_name from user_tab_columns t where t.table_name = l_tab_name)
    loop
      execute immediate 'select distinct ' || c1.column_name || ' from ' || l_tab_name;
    end loop;
end;

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