How to avoid 'unique constraint' error message when creating a view - sql

Question

I have a normal View and iam getting the error message :
[Error] Execution (6: 83): ORA-00604: error occurred at recursive SQL level 1
ORA-00001: unique constraint (SYS.I_COL1) violated
But I don't get what I am doing wrong. It says the bacl.Description, batl.Description, bagl.description are violating the uniqueness constraint.
CREATE OR REPLACE FORCE VIEW CCI.VW_TA04_BAC_PAGE_4_2 as
SELECT
bac.id,
bac.code code,
bacl.DESCRIPTION,
bac.order_key,
bac.bat_id,
batl.description,
bac.bag_id,
bagl.description,
bac.weight_factor,
bac.display
FROM BART_CATEGORIES bac,
BART_CATEGORIES_LAE bacl,
BART_CATEGORY_GROUPS bag,
BART_CATEGORY_GROUPS_LAE bagl,
BART_CATEGORY_TYPES bat,
BART_CATEGORY_TYPES_LAE batl
WHERE bacl.lae_id = pkg_process.language
AND batl.lae_id = pkg_process.language
AND bagl.lae_id = pkg_process.language
AND (bac.bag_id = bag.id)
AND (bac.bat_id = bat.id)
AND (bacl.BAC_ID = bac.id)
AND (bagl.BAG_ID = bag.id)
AND (batl.BAT_ID = bat.id)
Thanks for any advice.

Answer 1

" It says the bacl.Description, batl.Description, bagl.description are violating the uniqueness constraint"
Your view has columns with the same name from three different tables. Column name must be unique in the view. So you need to alias those columns. For instance this would do the trick:
CREATE OR REPLACE FORCE VIEW CCI.VW_TA04_BAC_PAGE_4_2 as
SELECT
bac.id,
bac.code code,
bacl.DESCRIPTION as bac_description,
bac.order_key,
bac.bat_id,
batl.description as bat_description,
bac.bag_id,
bagl.description as bag_description,
bac.weight_factor,
bac.display
" i tought writing "bacl" in front or would be enough."
We need both. The table alias tells the SQL engine which table provides the referenced value but it is not part of the column name.