How can I prevent SQL injection in PHP?

SQL query to aggregate result of a column comparison

Acothley

I have a SQL (Postgres) data structure that represents games for a group of matches. Table below shows that there have been 3 matches played (each consisting of either 2 or 3 games).

match_id player_one player_two p1_game_result p2_game_result 1 player1 player2 12 10 1 player1 player2 3 11 1 player1 player2 5 9 2 player1 player3 11 2 2 player1 player3 11 1 3 player2 player4 11 6 3 player2 player4 7 11 3 player2 player4 9 5

I want to group it by matchID to the following result table - each row should represent single match that will show how many games has each player won (which simply mean which out of 2 results column will be greater).

match_id player_one player_two p1_games_won p2_games_won 1 player1 player2 1 2 2 player1 player3 2 0 3 player2 player4 2 1

I'm aware how GROUP BY works, but I'm not able to use aggregate function that will apply required condition based on column values.

Query below counts games for each match only, without distinguishing how many games has each player won in a match.

SELECT
    g.match_id,
    g.player_one,
    g.player_two,
    count(*) as games_count
FROM games g
GROUP BY
    g.match_id,
    g.player_one,
    g.player_two;

Any help will be appreciated.