Index: java/engine/org/apache/derby/impl/sql/compile/ResultColumn.java =================================================================== --- java/engine/org/apache/derby/impl/sql/compile/ResultColumn.java (revision 628228) +++ java/engine/org/apache/derby/impl/sql/compile/ResultColumn.java (working copy) @@ -200,6 +200,28 @@ defaultColumn = value; } + /** + * Return TRUE if this result column matches the provided column name. + * + * This function is used by ORDER BY column resolution. For the + * ORDER BY clause, Derby will prefer to match on the column's + * alias (exposedName), but will also successfully match on the + * underlying column name. Thus the following statements are + * treated equally: + * select name from person order by name; + * select name as person_name from person order by name; + * select name as person_name from person order by person_name; + * See DERBY-2351 for more discussion. + */ + boolean columnNameMatches(String columnName) + { + if (columnName.equals(exposedName) || columnName.equals(name)) + return true; + if (expression instanceof ColumnReference && + columnName.equals(((ColumnReference)expression).getColumnName())) + return true; + return false; + } /** * The following methods implement the ResultColumnDescriptor * interface. See the Language Module Interface for details. Index: java/engine/org/apache/derby/impl/sql/compile/ResultColumnList.java =================================================================== --- java/engine/org/apache/derby/impl/sql/compile/ResultColumnList.java (revision 628228) +++ java/engine/org/apache/derby/impl/sql/compile/ResultColumnList.java (working copy) @@ -469,7 +469,7 @@ * should be removed from the ResultColumnList and returned * to the caller. */ - if (columnName.equals( resultColumn.getName()) ) + if (resultColumn.columnNameMatches(columnName)) { if (retVal == null) { @@ -573,7 +573,7 @@ /* We finally got past the qualifiers, now see if the column * names are equal. */ - if (columnName.equals( resultColumn.getName()) ) + if (resultColumn.columnNameMatches(columnName)) { if (retVal == null) { Index: java/testing/org/apache/derbyTesting/functionTests/tests/lang/orderby.sql =================================================================== --- java/testing/org/apache/derbyTesting/functionTests/tests/lang/orderby.sql (revision 628228) +++ java/testing/org/apache/derbyTesting/functionTests/tests/lang/orderby.sql (working copy) @@ -680,7 +680,26 @@ SELECT DISTINCT name FROM person ORDER BY name; -- This query should return two rows, ordered by name descending: SELECT DISTINCT name FROM person ORDER BY name desc; +-- Some test cases involving column aliasing: +select distinct name as first_name from person order by name; +select distinct name as first_name from person order by first_name; +select distinct person.name from person order by name; +select distinct name as first_name from person order by person.name; +select distinct name as age from person order by age; +select distinct name as age from person order by person.age; +select distinct name, name from person order by name; +select distinct name, name as first_name from person order by name; +select distinct name, name as first_name from person order by 2; +create table pets (name varchar(10), age int); +insert into pets values ('Rover', 3), ('Fido', 5), ('Buster', 1); +select distinct name from person union select distinct name from pets order by name; +select distinct name from person, pets order by name; +select distinct person.name as person_name, pets.name as pet_name from person,pets order by name; +select distinct person.name as person_name, pets.name from person,pets order by name; +select distinct person.name as name, pets.name as pet_name from person,pets order by name; +select distinct person.name as name, pets.name as pet_name from person,pets order by pets.name; drop table person; +drop table pets; create table d2887_types( Index: java/testing/org/apache/derbyTesting/functionTests/master/orderby.out =================================================================== --- java/testing/org/apache/derbyTesting/functionTests/master/orderby.out (revision 628228) +++ java/testing/org/apache/derbyTesting/functionTests/master/orderby.out (working copy) @@ -1759,8 +1759,82 @@ ---------- Mary John +ij> -- Some test cases involving column aliasing: +select distinct name as first_name from person order by name; +FIRST_NAME +---------- +John +Mary +ij> select distinct name as first_name from person order by first_name; +FIRST_NAME +---------- +John +Mary +ij> select distinct person.name from person order by name; +NAME +---------- +John +Mary +ij> select distinct name as first_name from person order by person.name; +FIRST_NAME +---------- +John +Mary +ij> select distinct name as age from person order by age; +AGE +---------- +John +Mary +ij> select distinct name as age from person order by person.age; +ERROR 42X79: Column name 'AGE' appears more than once in the result of the query expression. +ij> select distinct name, name from person order by name; +NAME |NAME +--------------------- +John |John +Mary |Mary +ij> select distinct name, name as first_name from person order by name; +NAME |FIRST_NAME +--------------------- +John |John +Mary |Mary +ij> select distinct name, name as first_name from person order by 2; +NAME |FIRST_NAME +--------------------- +John |John +Mary |Mary +ij> create table pets (name varchar(10), age int); +0 rows inserted/updated/deleted +ij> insert into pets values ('Rover', 3), ('Fido', 5), ('Buster', 1); +3 rows inserted/updated/deleted +ij> select distinct name from person union select distinct name from pets order by name; +NAME +---------- +Buster +Fido +John +Mary +Rover +ij> select distinct name from person, pets order by name; +ERROR 42X03: Column name 'NAME' is in more than one table in the FROM list. +ij> select distinct person.name as person_name, pets.name as pet_name from person,pets order by name; +ERROR 42X79: Column name 'NAME' appears more than once in the result of the query expression. +ij> select distinct person.name as person_name, pets.name from person,pets order by name; +ERROR 42X79: Column name 'NAME' appears more than once in the result of the query expression. +ij> select distinct person.name as name, pets.name as pet_name from person,pets order by name; +ERROR 42X79: Column name 'NAME' appears more than once in the result of the query expression. +ij> select distinct person.name as name, pets.name as pet_name from person,pets order by pets.name; +NAME |PET_NAME +--------------------- +John |Buster +Mary |Buster +John |Fido +Mary |Fido +John |Rover +Mary |Rover ij> drop table person; 0 rows inserted/updated/deleted +ij> drop table pets; +0 rows inserted/updated/deleted ij> create table d2887_types( id int, c1_smallint smallint, @@ -1903,4 +1977,4 @@ abc ij> drop table d2352; 0 rows inserted/updated/deleted -ij> +ij> \ No newline at end of file