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I'd like to convert single rows into multiple rows in PostgreSQL, where some of the columns are removed. Here's an example of the current output:

name | st | ot | dt |
-----|----|----|----|
Fred | 8  | 2  | 3  |
Jane | 8  | 1  | 0  |
Samm | 8  | 0  | 6  |  
Alex | 8  | 0  | 0  |  

Using the following query:

SELECT
   name, st, ot, dt
FROM
   times;

And here's what I want:

name |  t | val |
-----|----|-----|
Fred | st |  8  |
Fred | ot |  2  |
Fred | dt |  3  |
Jane | st |  8  |
Jane | ot |  1  |
Samm | st |  8  |
Samm | dt |  6  |
Alex | st |  8  |

How can I modify the query to get the above desired output?

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1 Answer

SELECT
  times.name, x.t, x.val
FROM
  times cross join lateral (values('st',st),('ot',ot),('dt',dt)) as x(t,val)
WHERE
  x.val <> 0;

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