How to add data from multiple tables

Question

I have a table for game stats. How do I add all the player's points from 18 different tables. I'm trying this but I get nothing, blank page.

 $result = mysqli_query($conn, "SELECT (SELECT kp.pts + kp2.pts2 + kp3.pts3 + kp4.pts4 + kp5.pts5 + kp6.pts6 + kp7.pts7 + kp8.pts8 + kp9.pts9  AS sum1 
FROM knightsplayer AS kp
JOIN knightsplayer2 AS kp2 ON kp.id = kp2.id2
JOIN knightsplayer3 AS kp3 ON kp.id = kp3.id3 
JOIN knightsplayer4 AS kp4 ON kp.id = kp4.id4 
JOIN knightsplayer5 AS kp5 ON kp.id = kp5.id5 
JOIN knightsplayer6 AS kp6 ON kp.id = kp6.id6 
JOIN knightsplayer7 AS kp7 ON kp.id = kp7.id7 
JOIN knightsplayer8 AS kp8 ON kp.id = kp8.id8 
JOIN knightsplayer9 AS kp9 ON kp.id = kp9.id9);

(SELECT bp.pts + bp2.pts2 + bp3.pts3 + bp4.pts4 + bp5.pts5 + bp6.pts6 + bp7.pts7 + bp8.pts8 + bp9.pts9  AS sum2 
FROM blazersplayer AS bp
JOIN blazersplayer2 AS bp2 ON bp.id = bp2.id2
JOIN blazersplayer3 AS bp3 ON bp.id = bp3.id3 
JOIN blazersplayer4 AS bp4 ON bp.id = bp4.id4 
JOIN blazersplayer5 AS bp5 ON bp.id = bp5.id5 
JOIN blazersplayer6 AS bp6 ON bp.id = bp6.id6 
JOIN blazersplayer7 AS bp7 ON bp.id = bp7.id7 
JOIN blazersplayer8 AS bp8 ON bp.id = bp8.id8 
JOIN blazersplayer9 AS bp9 ON bp.id = bp9.id9)");

Each table is for one game, so knightsplayer is the stats for the first game for the team "Knights". knightsplayer2 is the stats for the second game and so on. I have to add all the points of the individual players from both teams and display them as one table. Basically a leader board for points.

Answer 1

I suggest you to migrate data to the next strcuture:

-- ----------------------------
-- Table structure for game
-- ----------------------------
DROP TABLE IF EXISTS `game`;
CREATE TABLE `game` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(128) DEFAULT NULL,
  `active` tinyint(1) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of game
-- ----------------------------
INSERT INTO `game` VALUES ('1', 'knights', '1');
INSERT INTO `game` VALUES ('2', 'blazers', '1');

-- ----------------------------
-- Table structure for player
-- ----------------------------
DROP TABLE IF EXISTS `player`;
CREATE TABLE `player` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(64) DEFAULT NULL,
  `active` tinyint(1) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of player
-- ----------------------------
INSERT INTO `player` VALUES ('1', 'player1', '1');
INSERT INTO `player` VALUES ('2', 'player2', '1');
INSERT INTO `player` VALUES ('3', 'player3', '1');
INSERT INTO `player` VALUES ('4', 'player4', '1');
INSERT INTO `player` VALUES ('5', 'player5', '1');
INSERT INTO `player` VALUES ('6', 'player6', '1');
INSERT INTO `player` VALUES ('7', 'player7', '1');
INSERT INTO `player` VALUES ('8', 'player8', '1');
INSERT INTO `player` VALUES ('9', 'player9', '1');

-- ----------------------------
-- Table structure for statistics
-- ----------------------------
DROP TABLE IF EXISTS `statistics`;
CREATE TABLE `statistics` (
  `game_id` int(11) DEFAULT NULL,
  `player_id` int(11) DEFAULT NULL,
  `points` decimal(10,2) DEFAULT NULL,
  KEY `player_fk` (`player_id`),
  KEY `game_fk` (`game_id`),
  CONSTRAINT `game_fk` FOREIGN KEY (`game_id`) REFERENCES `game` (`id`) ON DELETE SET NULL ON UPDATE NO ACTION,
  CONSTRAINT `player_fk` FOREIGN KEY (`player_id`) REFERENCES `player` (`id`) ON DELETE SET NULL ON UPDATE NO ACTION
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of statistics
-- ----------------------------
INSERT INTO `statistics` VALUES ('1', '3', '23.00');
INSERT INTO `statistics` VALUES ('1', '1', '345.00');
INSERT INTO `statistics` VALUES ('1', '4', '4.00');
INSERT INTO `statistics` VALUES ('1', '2', '345.00');
INSERT INTO `statistics` VALUES ('1', '5', '23.00');
INSERT INTO `statistics` VALUES ('1', '6', '445.00');
INSERT INTO `statistics` VALUES ('1', '7', '47.00');
INSERT INTO `statistics` VALUES ('1', '8', '5.00');
INSERT INTO `statistics` VALUES ('1', '9', '523.00');
INSERT INTO `statistics` VALUES ('2', '1', '2341.00');
INSERT INTO `statistics` VALUES ('2', '2', '0.00');
INSERT INTO `statistics` VALUES ('2', '3', '56.00');
INSERT INTO `statistics` VALUES ('2', '4', '756.00');
INSERT INTO `statistics` VALUES ('2', '5', '755.00');
INSERT INTO `statistics` VALUES ('2', '6', '56.00');
INSERT INTO `statistics` VALUES ('2', '7', '345.00');
INSERT INTO `statistics` VALUES ('2', '8', '523.00');
INSERT INTO `statistics` VALUES ('2', '9', '12.00');

Then your can query:

SELECT
game.`name`,
SUM(statistics.points)
FROM
statistics
INNER JOIN game ON game.id = statistics.game_id
GROUP BY game.`id`

Answer 2

You have a subquery in your SELECT clause, but you don't have a FROM clause to complete the outer query.

Also, the ; between the two subqueries, denotes the end of the SQL statement.

You can do something like:

SELECT sum1, sum2
FROM (subquery1 here) as table1,
     (subquery2 here) as table2;

As in (using your example):

"SELECT sum1, sum2
 FROM (SELECT kp.pts + kp2.pts2 + kp3.pts3 + kp4.pts4 + kp5.pts5 + kp6.pts6 + kp7.pts7 + kp8.pts8 + kp9.pts9  AS sum1 
       FROM knightsplayer AS kp
       JOIN knightsplayer2 AS kp2 ON kp.id = kp2.id2
       JOIN knightsplayer3 AS kp3 ON kp.id = kp3.id3 
       JOIN knightsplayer4 AS kp4 ON kp.id = kp4.id4 
       JOIN knightsplayer5 AS kp5 ON kp.id = kp5.id5 
       JOIN knightsplayer6 AS kp6 ON kp.id = kp6.id6 
       JOIN knightsplayer7 AS kp7 ON kp.id = kp7.id7 
       JOIN knightsplayer8 AS kp8 ON kp.id = kp8.id8 
       JOIN knightsplayer9 AS kp9 ON kp.id = kp9.id9) as table1,
      (SELECT bp.pts + bp2.pts2 + bp3.pts3 + bp4.pts4 + bp5.pts5 + bp6.pts6 + bp7.pts7 + bp8.pts8 + bp9.pts9  AS sum2 
       FROM blazersplayer AS bp
       JOIN blazersplayer2 AS bp2 ON bp.id = bp2.id2
       JOIN blazersplayer3 AS bp3 ON bp.id = bp3.id3 
       JOIN blazersplayer4 AS bp4 ON bp.id = bp4.id4 
       JOIN blazersplayer5 AS bp5 ON bp.id = bp5.id5 
       JOIN blazersplayer6 AS bp6 ON bp.id = bp6.id6 
       JOIN blazersplayer7 AS bp7 ON bp.id = bp7.id7 
       JOIN blazersplayer8 AS bp8 ON bp.id = bp8.id8 
       JOIN blazersplayer9 AS bp9 ON bp.id = bp9.id9) as table2;"

Or, if you need to join the two inline views:

SELECT sum1, sum2
FROM (subquery1 here) as table1 
JOIN (subquery2 here) as table2
ON (join condition); 

Keep in mind that if you do need to join the two inline views, you need to select a column (aside from sum1/sum2) to join on.