choose minimum date from a record out of multiple columns

db2, sql

Solution

SELECT person AS the_person
  , LEAST(date1 ,date2, date3, date4, date5, ..., dateN ) AS the_date
FROM the_table ;

`Least()` should ignore NULLs, if present. (the above works for Postgres)

UPDATE (thanks to @WarrenT) apparently DB2 does not have `LEAST()`, but it does have `MIN()` instead (having more than one argument).

SELECT person AS the_person
  , MIN(date1 ,date2, date3, date4, date5, ..., dateN ) AS the_date
FROM the_table ;

Problem

Hi I have the following table struct: ``` Person Date1 Date2............Daten ------ ----- ----- ----- 1 2001-01-01 2002-01-01 2 2003-01-01 2000-01-01 ``` and i want to choose the minimum Date between Date1 and Date(n) (20 dates in my case). So for example it would choose Date1 for Person1 and Date2 for Person2. obviously i can just use min(Date) if I only have 1 date columns, but I can't get my logic right in this case. Thanks very much.

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