sql - Is it possible to count all rows with the same id with COUNT? -


postgresql 9.4.

i have following table:

   id             player_id serial pk          integer ---------------------------    1                  1    2                  3   ...                ...  123123               1

i need count rows player_id = 1. possible count aggregate?

now follows:

sum(case when player_id = 1 1 else 0 end)

if need count of number of rows player_id 1, can this:

select count(*) your_table_name player_id = 1;

if want count number of rows each player_id, need use group by:

select player_id, count(*) your_table_name group player_id;

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