Oracle SQL Find First Match from single table [closed] - sql

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I have a table that lists concurrent program IDs and names. However, the table allows more than one name for each program ID. I'm needing to report some data about the programs, but am having trouble getting it to display correctly, as the program name is what is being displayed and grouped by in Tableau.
So what I need is a way to pull the first name for each program ID from the table. Since I'm including the program name in my output, I can't use unique (it wouldn't filter the alternate names) & I can't use a join as there wouldn't be a unique match.

Answer 1

Several options (of varying efficiency) to get the (alphabetically) first name for each id.
SQL Fiddle
Oracle 11g R2 Schema Setup:
CREATE TABLE PROGRAMS ( ID, NAME ) AS
SELECT 1, 'Charlie' FROM DUAL
UNION ALL SELECT 1, 'Bob' FROM DUAL
UNION ALL SELECT 1, 'Alice' FROM DUAL
UNION ALL SELECT 2, 'Ed' FROM DUAL
UNION ALL SELECT 2, 'Doris' FROM DUAL
UNION ALL SELECT 3, 'Fern' FROM DUAL
UNION ALL SELECT 3, 'Godfrey' FROM DUAL;
Query 1:
SELECT ID,
MIN( NAME ) AS NAME
FROM PROGRAMS
GROUP BY ID
ORDER BY ID
Results:
| ID | NAME |
|----|-------|
| 1 | Alice |
| 2 | Doris |
| 3 | Fern |
Query 2:
SELECT DISTINCT
ID,
FIRST_VALUE( NAME ) OVER ( PARTITION BY ID ORDER BY NULL ) AS NAME
FROM PROGRAMS
ORDER BY ID
Results:
| ID | NAME |
|----|-------|
| 1 | Alice |
| 2 | Doris |
| 3 | Fern |
Query 3:
SELECT ID,
NAME
FROM PROGRAMS p
WHERE NOT EXISTS ( SELECT 'X'
FROM PROGRAMS x
WHERE p.ID = x.ID
AND p.NAME > x.NAME )
ORDER BY ID
Results:
| ID | NAME |
|----|-------|
| 1 | Alice |
| 2 | Doris |
| 3 | Fern |