Format:

column column_name new_value var_name

Meaning:

use the column_name of a select statment to construct a variable, later we can use &var_name to refer its value.

If the Select statement returned more that one row, the last row value will be assigned  to the variable.

Example 1:

-- create directory and varchar2 array

col value new_value user_dump_directory;

select value from v$parameter where name = 'user_dump_dest';

create or replace directory user_dump_dir as '&user_dump_directory';

Example 2

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create table new_value_test_from (

  some_field_name Varchar2(20)

);

create table new_value_test_to (

  another_field Varchar2(20)

);

insert into new_value_test_from values ('Maegerli Mucki');
column some_field_name new_value some_var_name

select some_field_name from new_value_test_from;

insert into new_value_test_to values ('&some_var_name');

select * from new_value_test_to;

drop table new_value_test_from;

drop table new_value_test_to;

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create table new_value_test (

  some_field_name Varchar2(20)

);

Example 3

insert into new_value_test values ('Maegerli Mucki');

insert into new_value_test values ('Globi');
column some_field_name new_value some_var_name

select some_field_name from new_value_test;

drop table new_value_test;