Select Row Number in Postgres

How to show row numbers in PostgreSQL query?

select   row_number() over (order by <field> nulls last) as rownum, *
from     foo_tbl
order by <field>

If order is not necessary, this answer may also be simplified:

select row_number() over(), *  -- notice: no fields are needed
from   foo_tbl

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SQL Fiddle Proof of Concept

Rownum in postgresql

Postgresql > 8.4

SELECT 
    row_number() OVER (ORDER BY col1) AS i, 
    e.col1, 
    e.col2, 
    ... 
FROM ... 

Row_number() in postgresql

Postgres does allow the syntax:

select row_number() over (), . . .

However, that does not necessary return the row numbers in the ordering specified by the outer order by. I think Postgres calculates the row number before the order by.

You might be tempted to use:

select row_number() over (), . . .
from (select . . . 
      from . . .
      order by  . . .
     ) t;

And, this would seem to do what you want (one a single processor machine, for instance, it just did the right thing). However, this is not guaranteed to work. The ordering in a subquery does not apply to the outer query (although this might only be visible on multi-processor machines).

My advice? Simply repeat the order by twice (using either the expression or the alias). That is guaranteed to work. And, you might be surprised at the optimizer only needing to sort the data once.

Using ROW_NUMBER() Function in a WHERE statement in Postgres

Because window functions, like row_number(), are applied to the result of the query (in your case that's the inner one), i.e. after the WHERE clause (not statement) has already taken effect.

Postgres: How to get row number when ordered by the result of operation?

Try:

WITH summary AS (
    SELECT
        i.id,
        i.pos - i.neg AS diff,
        ROW_NUMBER() OVER(ORDER BY (i.pos - i.neg)) AS position
    FROM items i)
SELECT s.*  FROM summary s WHERE s.id = 351435254

How to assign row number using row_number() to a repeated values in postgresql

You want:

WITH cte AS (
    SELECT *, ROW_NUMBER() OVER (PARTITION BY agentid, customerid ORDER BY random()) rn,
              COUNT(*) OVER (PARTITION BY agentid, customerid) cnt
    FROM aa_dev.calls
)

SELECT agentid, customerid, rn      
FROM cte
WHERE cnt > 1;

Get row number of a row that meets an x condition in Postgresql

I guess I rushed a little. Sorry.
I already found the solution. The following query worked for me:

SELECT num FROM (SELECT Row_Number() OVER () AS num, country FROM people ORDER BY country) AS tabla WHERE country='France'

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