Joining two select queries from the same table

Question

The table contains an ID column, valueHeading column and a value column. I want to separate the value column into two new columns called valueHeading1 and valueHeading2 depending on which type of valueHeading the value has.

So I want to join this select: Edit: Full join

SELECT ID
      ,valueHeading
      ,value as 'valueHeading1'
FROM table1
WHERE valueHeading = 'valueHeading1'

With This select:

SELECT ID
      ,value as 'valueHeading2'
FROM table1
WHERE valueHeading = 'valueHeading2'

on their respective ID's. How do I do this?

Edit to illustrate what I want to do:

Original table:

ID    valueHeading    value
0     valueHeading1    a
0     valueHeading2    a
1     valueHeading1    ab
1     valueHeading2    NULL
2     valueHeading1    abcd
2     valueHeading2    abc

New Table:

ID    valueHeading1    valueHeading2
0          a               a
1          ab              NULL
2         abcd             abc

Answer 1

Try something like :

SELECT ID
      , CASE WHEN valueHeading = 'valueHeading1' THEN value ELSE NULL END AS valueHeading1
      , CASE WHEN valueHeading = 'valueHeading2' THEN value ELSE NULL END AS valueHeading2
FROM table1
WHERE valueHeading IN ('valueHeading1', 'valueHeading2')

If you want to regroup all values on one row for each ID, you can try :

SELECT ID
      , MAX(CASE WHEN valueHeading = 'valueHeading1' THEN value ELSE NULL END) AS valueHeading1
      , MAX(CASE WHEN valueHeading = 'valueHeading2' THEN value ELSE NULL END) AS valueHeading2
FROM table1
WHERE valueHeading IN ('valueHeading1', 'valueHeading2')
GROUP BY ID
HAVING MAX(CASE WHEN valueHeading = 'valueHeading1' THEN value ELSE NULL END) IS NOT NULL
OR MAX(CASE WHEN valueHeading = 'valueHeading2' THEN value ELSE NULL END) IS NOT NULL

See SQLFiddle. I also tried on Oracle 11g and MSSQL 2012, and it works each time.