Question

Problem

There are data gaps that need to be filled. Would like to avoid UNION or PARTITION BY if possible.

Query Statement

The select statement reads as follows:

SELECT
  count( r.incident_id ) AS incident_tally,
  r.severity_cd,
  r.incident_typ_cd
FROM
  report_vw r
GROUP BY
  r.severity_cd, r.incident_typ_cd
ORDER BY
  r.severity_cd,
  r.incident_typ_cd

Data Sources

The severity codes and incident type codes are from:

• severity_vw
• incident_type_vw

The columns are:

• incident_tally
• severity_cd
• incident_typ_cd

Actual Result Data

36  0   ENVIRONMENT
1   1   DISASTER
27  1   ENVIRONMENT
4   2   SAFETY
1   3   SAFETY

Required Result Data

36  0   ENVIRONMENT
0   0   DISASTER
0   0   SAFETY
27  1   ENVIRONMENT
0   1   DISASTER
0   1   SAFETY
0   2   ENVIRONMENT
0   2   DISASTER
4   2   SAFETY
0   3   ENVIRONMENT
0   3   DISASTER
1   3   SAFETY

Question

How would you use UNION, PARTITION BY, or LEFT JOIN to fill in the zero counts?

Answer 1

How about something like

SELECT  COUNT(r.incident_id),
        crsjn.severity_cd,
        crsjn.incident_typ_cd
FROM    (
            SELECT  severity_cd,
                    incident_typ_cd
            FROM    severity_vw,
                    incident_type_vw
        ) crsjn LEFT JOIN
        report_vw r     ON  crsjn.severity_cd = r.severity_cd 
                        AND crsjn.incident_typ_cd = r.incident_typ_cd
GROUP BY crsjn.severity_cd,
        crsjn.incident_typ_cd
ORDER BY crsjn.severity_cd,
        crsjn.incident_typ_cd