pivoting, crosstabbing and almost there !

Hi,
I am trying to get a pivoted result from a query. The
pivoting works, however I want to eliminate
some of the rows, which have no value at all in every
column but the name column.

Current result:
name first second third
bill
bob 90
sue 85 90 95

desired:
name first second third
bob 90
sue 85 90 95

Of course this example is extremly oversimplified. I
will not know the actual exams values, but retrieve
them
dynamically. I know that there is a patch now for
doing crosstabs (thanks!), but a more general SQL
solution would
be better ( maybe it will have to run on other dbs ).

Thank you very much for your answers.

robert

Example code:

CREATE TABLE students ( name varchar(10), NOT NULL
UNIQUE, PRIMARY KEY( name ) );
CREATE TABLE exams( exam varchar(10) NOT NULL UNIQUE,
PRIMARY KEY( exam ) );
CREATE TABLE scores( name varchar(10), exam
varchar(10), score int,
FOREIGN KEY (name) REFERENCES students, FOREIGN KEY(
exam ) REFERENCES exams );

INSERT INTO students VALUES ( 'Bill' );
INSERT INTO students VALUES ('Bob');
INSERT INTO students VALUES ('Sue');

INSERT INTO exams VALUES( 'first' );
INSERT INTO exams VALUES( 'second' );
INSERT INTO exams VALUES('third');

INSERT INTO scores VALUES( 'Bill', 'first', 50 );
INSERT INTO scores VALUES( 'Bill', 'second', 60 );
INSERT INTO scores VALUES( 'Bill', 'third', 55 );
INSERT INTO scores VALUES( 'Bob', 'first', 70 );
INSERT INTO scores VALUES( 'Bob', 'second', 90 );
INSERT INTO scores VALUES( 'Bob', 'third', 85 );
INSERT INTO scores VALUES( 'Sue', 'first', 85 );
INSERT INTO scores VALUES( 'Sue', 'second', 90 );
INSERT INTO scores VALUES( 'Sue', 'third', 95 );

SELECT students.name,
( SELECT score FROM scores
WHERE (
students.name = scores.name
AND
scores.exam = 'first'
AND
scores.score > '70'
)
) AS first,
( SELECT score FROM scores
WHERE (
students.name = scores.name
AND
scores.exam = 'second'
AND
scores.score > '80'
)
) AS second,
( SELECT score FROM scores
WHERE (
students.name = scores.name
AND
scores.exam = 'third'
AND
scores.score > '90'
)
) AS third
FROM students;

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