Kann mir jemand helfen diese Abfrage zu optimieren

<code>SELECT 
  `debit_side`.`account_code` CODE,
  GROUP_CONCAT(DISTINCT accounts.name) AS DebitAccount,
  GROUP_CONCAT(debit_side.amount) AS DebitAmount,
  GROUP_CONCAT(transaction_info.voucher_date) AS DebitVoucherDate,
  (SELECT 
    GROUP_CONCAT(DISTINCT accounts.name) 
  FROM
    (accounts) 
    LEFT JOIN debit_side 
      ON accounts.code = debit_side.account_code 
    LEFT JOIN credit_side 
      ON debit_side.transaction_id_dr = credit_side.transaction_id_cr 
    LEFT JOIN transaction_info 
      ON transaction_info.transaction_id = credit_side.transaction_id_cr 
  GROUP BY credit_side.account_code 
  HAVING credit_side.account_code = `Code`) AS CreditAccount,
  (SELECT 
    GROUP_CONCAT(credit_side.amount) AS CreditAmount 
  FROM
    (accounts) 
    LEFT JOIN debit_side 
      ON accounts.code = debit_side.account_code 
    LEFT JOIN credit_side 
      ON debit_side.transaction_id_dr = credit_side.transaction_id_cr 
    LEFT JOIN transaction_info 
      ON transaction_info.transaction_id = credit_side.transaction_id_cr 
  GROUP BY credit_side.account_code 
  HAVING credit_side.account_code = `Code`) AS CreditAmount,
  (SELECT 
    GROUP_CONCAT(transaction_info.voucher_date) AS CreditVoucherDate 
  FROM
    (accounts) 
    LEFT JOIN debit_side 
      ON accounts.code = debit_side.account_code 
    LEFT JOIN credit_side 
      ON debit_side.transaction_id_dr = credit_side.transaction_id_cr 
    LEFT JOIN transaction_info 
      ON transaction_info.transaction_id = credit_side.transaction_id_cr 
  GROUP BY credit_side.account_code 
  HAVING credit_side.account_code = `Code`) AS CreditVoucherDate 
FROM
  (`accounts`) 
  LEFT JOIN `credit_side` 
    ON `accounts`.`code` = `credit_side`.`account_code` 
  LEFT JOIN `debit_side` 
    ON `debit_side`.`transaction_id_dr` = `credit_side`.`transaction_id_cr` 
  LEFT JOIN `transaction_info` 
    ON `transaction_info`.`transaction_id` = `credit_side`.`transaction_id_cr` 
GROUP BY `debit_side`.`account_code` 
HAVING `Code` IS NOT NULL 
ORDER BY `debit_side`.`account_code` ASC 
</code>

Tatsächlich versuche ich in dieser Abfrage, Daten für Debit- und Kreditseite für alle Konten abzurufen. Sie müssen bemerkt haben, dass Unterabfragen wiederholt werden, aber unterschiedliche Spalten auswählen. Diese Abfrage holt perfekte Ergebnisse, aber ich möchte, dass es optimiert wird. Hier ist der Link zu meinem Schema

http://www.sqlfiddle.com/#!2/82274/6

Zuvor hatte ich diese beiden Abfragen, die ich zu kombinieren versuchte

<code>SELECT
  debit_side.account_code    DebitCode,
  group_concat(distinct accounts.name) as DebitAccount,
  group_concat(debit_side.amount) as DebitAmount,
  group_concat(transaction_info.voucher_date) as DebitVoucherDate
FROM (`accounts`)
  LEFT JOIN `credit_side`
    ON `accounts`.`code` = `credit_side`.`account_code`
  LEFT JOIN `debit_side`
    ON `debit_side`.`transaction_id_dr` = `credit_side`.`transaction_id_cr`
  LEFT JOIN `transaction_info`
    ON `transaction_info`.`transaction_id` = `credit_side`.`transaction_id_cr`
GROUP BY `debit_side`.`account_code`
ORDER BY `debit_side`.`account_code` ASC
</code>

Und

<code>SELECT
  credit_side.account_code    CreditCode,
  group_concat(distinct accounts.name) as CreditAccount,
  group_concat(credit_side.amount) as CreditAmount,
  group_concat(transaction_info.voucher_date) as CreditVoucherDate
FROM (`accounts`)
  LEFT JOIN `debit_side`
    ON `accounts`.`code` = `debit_side`.`account_code`
  LEFT JOIN `credit_side`
    ON `debit_side`.`transaction_id_dr` = `credit_side`.`transaction_id_cr`
  LEFT JOIN `transaction_info`
    ON `transaction_info`.`transaction_id` = `credit_side`.`transaction_id_cr`
GROUP BY `credit_side`.`account_code`
ORDER BY `credit_side`.`account_code` ASC
</code>

Auch ich möchte nullsatz entfernen, der geholt wird. Anmerkung: Sie sollten auch beachten, dass ich in den Unterabfragen ein bisschen andere Bedingungen verwende, die sich gemäß meinen Anforderungen ergeben.

EDITS

Ich habe das Problem behoben, den Nulldatensatz zu entfernen, aber die Optimierung wurde beibehalten.

NEUE EDITS

Hier ist was ich mit semi join ausprobiert habe

<code>SELECT
  `lds`.`account_code`    DebitCode,
  group_concat(distinct la.name) as DebitAccount,
  group_concat(lds.amount) as DebitAmount,
  group_concat(lti.voucher_date) as DebitVoucherDate,
  `rcs`.`account_code`    CreditCode,
  group_concat(distinct ra.name) as CreditAccount,
  group_concat(rcs.amount) as CreditAmount,
  group_concat(rti.voucher_date) as CreditVoucherDate
FROM accounts as la
  LEFT join accounts as ra
    ON ra.`code` = la.`code`
  LEFT JOIN `credit_side` as lcs
    ON `la`.`code` = `lcs`.`account_code`
  LEFT JOIN `debit_side` as lds
    ON `lds`.`transaction_id_dr` = `lcs`.`transaction_id_cr`
  LEFT JOIN `transaction_info` as lti
    ON `lti`.`transaction_id` = `lcs`.`transaction_id_cr`
  LEFT JOIN `debit_side` as rds
    ON `ra`.`code` = `rds`.`account_code`
  LEFT JOIN `credit_side` rcs
    ON `rds`.`transaction_id_dr` = `rcs`.`transaction_id_cr`
  LEFT JOIN `transaction_info` as rti
    ON `rti`.`transaction_id` = `rcs`.`transaction_id_cr`
GROUP BY `CreditCode`
HAVING `CreditCode` IS NOT NULL
ORDER BY `CreditCode` ASC
</code>

Das Seltsame ist, dass wenn ich die Gruppe ändere, indem ich DebitCode habe und danach bestelle, es perfekte Datensätze für die Debitseite bringt, und wenn ich dies mit CreditCode ändere, wenn es perfekte Datensätze für die Kreditseite bringt. Gibt es eine Möglichkeit, dieses Problem oder eine Alternative zu überwinden.