Question

I have written PLSQL program that generates table having usually more than 200 columns.
It’s number of columns is not fixed and it changes every time plsql procedure is executed.
I always need to SELECT not all the columns but it is cumbersome to add them into SELECT query by hand. The columns that I don’t need to select are column1, column2 and column3 every time. IF I have 200 columns I need to write

Select column4, column5, ..., column200 from plsqltable

My solution is to use another PLSQL program to look for column names from user_tab_colums (system view) for that table and compose that sql query. Is there some simpler way to achieve the same sql? Usally I write SELECT table.* FROM table; if I want to see all columns. Is there a way to use similar syntax to say that SELECT all but not table.col1, table.col2, table.col3 FROM table;?

Answer 1

http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:766825833740

Pivot table oracle with unknown number
of rows to be pivot

…

Followup October 31, 2006 – 6pm Central time zone:

you would have to

a) run a query to determine the number of columns

b) use that information to build a dynamic sql query that does that.

so this is what I did, and you shouldn’t need a second procedure to do this; you can do it right in your main procedure:

DROP TABLE dynamic_built_table;

CREATE TABLE dynamic_built_table
  (
    column1 VARCHAR2(1),
    column2 VARCHAR2(1),
    column3 VARCHAR2(1),
    column4 VARCHAR2(1),
    column5 VARCHAR2(1),
    column6 VARCHAR2(1)
  );

DECLARE
  l_sql VARCHAR2(5000);
BEGIN
  l_sql         := 'CREATE OR REPLACE VIEW DYNAMIC_COLUMN_VIEW AS SELECT ';
  FOR l_columns IN
  (SELECT column_name,
      column_id,
      MAX(column_id) over (partition BY table_name) max_column
    FROM user_tab_cols
    WHERE table_name = 'DYNAMIC_BUILT_TABLE'
    AND column_id    > 3
  )
  LOOP
    l_sql                  := l_sql||l_columns.column_name;
    IF l_columns.column_id != l_columns.max_column THEN
      l_sql                := l_sql||',';
    END IF;
  END LOOP;
  l_sql := l_sql||' from dynamic_built_table';
  EXECUTE immediate l_sql;
END;
/

SELECT * FROM DYNAMIC_COLUMN_VIEW;