SAP S/4HANA Error 2865: Duplicate SQLScript Attribute Name

Example of a potential duplicate:

@AbapCatalog.sqlViewName: 'MYVIEW'
@AbapCatalog.compiler.compareFilter: true
@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'My View'
define view Z_MY_DUPLICATE_VIEW as select from my_table1 as t1
  join my_table2 as t2 on t1.key = t2.key
{
  t1.field1 as common_field,
  t2.field2 as common_field, -- Duplicate attribute name
  t1.field3
}

Corrected example:

@AbapCatalog.sqlViewName: 'MYVIEW'
@AbapCatalog.compiler.compareFilter: true
@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'My View'
define view Z_MY_DUPLICATE_VIEW as select from my_table1 as t1
  join my_table2 as t2 on t1.key = t2.key
{
  t1.field1 as unique_field_from_t1,
  t2.field2 as unique_field_from_t2, -- Renamed attribute
  t1.field3
}

Example of a duplicate in a SQL script:

CREATE PROCEDURE MY_PROCEDURE ()
BEGIN
  DECLARE my_value INT;
  SELECT COUNT(*) INTO my_value FROM my_table1;
  SELECT my_value AS result, COUNT(*) AS result FROM my_table2; -- Duplicate 'result' alias
END;

Corrected example:

CREATE PROCEDURE MY_PROCEDURE ()
BEGIN
  DECLARE count_from_table1 INT;
  SELECT COUNT(*) INTO count_from_table1 FROM my_table1;
  SELECT count_from_table1 AS result_table1, COUNT(*) AS result_table2 FROM my_table2; -- Renamed aliases
END;

Best practice example:

define view Z_CLEAR_VIEW as select from my_table1 as t1
  join my_table2 as t2 on t1.key = t2.key
{
  t1.field1 as t1_field1, -- Explicit alias
  t2.field2 as t2_field2, -- Explicit alias
  t1.field3 as t1_field3
}