MySQL表联接2个表

Question

i have two tables in mySQL:

Table 1: Club(ClubID=PK, club_name)

Table 2: League_table(tableID=PK, position, clubID=fk, games_played, points)

how would i join the two tables to give a query that displayed only

(position, club-name, games_played)

Answer 1

Simple join:

select l.position, c.club_name, l.games_played
from club c, league_table l 
where l.clubid=c.clubid

Answer 2

You are looking for a left join. ClubID is the foreign key (the column "connecting" the two tables).

select position, club_name, games_played
from league_table
left join club on club.ClubId = league_table.clubID

Answer 3

select a.club_name, b.position, b.games_played from club as a join league_table as b on a.clubid=b.clubid Thats what you want.

@Alexen: No need of left join in this case.

@Diegoe: one friendly advise, always use on in join, without it query goes slow down when you are working on big tables.