MYSQL: How to find player_id from surname? - mysql

Question

I'm now trying to populate my 'testMatch' table (below) with data from my unormalised 'summary' table:
TESTMATCH TABLE
+------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------+--------------+------+-----+---------+-------+
| match_id | int(11) | NO | PRI | NULL | |
| match_date | date | YES | | NULL | |
| ground | varchar(50) | YES | MUL | NULL | |
| homeTeam | varchar(100) | YES | MUL | NULL | |
| awayTeam | varchar(100) | YES | MUL | NULL | |
| matchResult | varchar(100) | YES | MUL | NULL | |
| manOfMatch | varchar(30) | YES | | NULL | |
| homeTeam_captain | int(10) | YES | MUL | NULL | |
| homeTeam_keeper | int(10) | YES | MUL | NULL | |
| awayTeam_captain | int(10) | YES | MUL | NULL | |
| awayTeam_keeper | int(10) | YES | MUL | NULL | |
+------------------+--------------+------+-----+---------+-------+
There is no problem populating match_id -----> manOfMatch - it is 'homeTeam_captain', 'homeTeam_keeper', 'awayTeam_captain' and 'awayTeam_keeper' that i'm having problems bringing in.
SUMMARY TABLE
mysql> DESCRIBE SUMMARY;
+-----------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+--------------+------+-----+---------+-------+
| matchID | int(11) | NO | PRI | NULL | |
| Test | int(11) | YES | | NULL | |
| matchDate | date | YES | | NULL | |
| Ground | varchar(50) | YES | | NULL | |
| HomeTeam | varchar(100) | YES | | NULL | |
| AwayTeam | varchar(100) | YES | | NULL | |
| matchResult | varchar(50) | YES | | NULL | |
| MarginRuns | int(11) | YES | | NULL | |
| MarginWickets | int(11) | YES | | NULL | |
| ManOfMatch | varchar(40) | YES | | NULL | |
| HomeTeamCaptain | varchar(30) | YES | | NULL | |
| HomeTeamKeeper | varchar(30) | YES | | NULL | |
| AwayTeamCaptain | varchar(30) | YES | | NULL | |
| AwayTeamKeeper | varchar(30) | YES | | NULL | |
+-----------------+--------------+------+-----+---------+-------+
I need to somehow select the data from summary, get the corresponding player_id and input the player_id into my 'testMatch'. Player table below:
PLAYERS TABLE
mysql> describe players;
+----------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+----------------+
| player_id | int(11) | NO | PRI | NULL | auto_increment |
| player_surname | varchar(30) | YES | | NULL | |
| team | varchar(100) | YES | MUL | NULL | |
+----------------+--------------+------+-----+---------+----------------+
So to clarify, eg. I want to select homeTeam_captain data FROM summary table BUT not the name, I want the corresponding player_id instead.
I assume I need to use some sort of join/subqueries to get this done... i've tried selecting with:
select matchID, player_id, player_surname, team from players p, summary s
where
s.hometeamcaptain = p.player_surname ORDER BY matchID;
but this brings back 73 rows and there should only be 65 (65 matches).
I hope this makes sense and thanks for your help!!
Theresa

Answer 1

Are there overlapping names? If so, also assure that the teams correspond (add s.HomeTeam = p.team to the where block). If there are players with the same name in one team, you will have to solve these conflicts manually.
To select all the keepers/captains at once, you need left outer joins. I guess it will be one join per player, so you have to join the same table 4 times.
Once you've selected the right data, you can insert it in your testMatch table with INSERT ... SELECT.