Oracle 11g 查询需要将近 30 分钟才能完成，但在 SQL Server 中大约需要 5 分钟

Question

I need to produce a details report of user that using prepaid.

Basically I have 2 tables. TBL_USER and also TBL_PREPAID_DETAILS

tbl_user only list the users while tbl_prepaid_details will have all the prepaid information such as debit, credit, balance, total topup.

The report will be produced something like this:-

FULLNAME USER_ID NEW_BALANCE CREATED DEPOSIT DEBIT TOTAL_DEPOSIT
USER1 1 250 21/05/2011 500 250 1000
USER2 2 250 21/05/2011 500 250 1000
USER3 3 250 21/05/2011 500 250 1000
USER4 4 250 21/05/2011 500 250 1000

Before this I'm using SQL server for database but for the year 2012/2013 we need to migrate from SQL server to Oracle 11g.

From the previous sql query (SQL Server), I come out with below query (Oracle 11g). I can get the result but it took almost 30min to finish while in SQL server only took around 5min. Its only 500+ users

Is it i'm missing something?? Is there any simplified version to speed up the process ?

SELECT DISTINCT A.FULLNAME AS NAME,
                A.USER_ID AS ID,
                B.NAME,

  (SELECT T.NEW_BAL
   FROM
     (SELECT NEW_BAL,
             USER_ID
      FROM TBL_PREPAID_DETAILS
      WHERE DATE_INSERT BETWEEN '01/01/2010' AND '14/11/2012'
      ORDER BY PREPAID_DETAIL_ID DESC) T
   WHERE T.USER_ID = A.USER_ID
     AND ROWNUM = 1) AS NEW_BALANCE,

  (SELECT T2.DATE_INSERT
   FROM
     (SELECT DATE_INSERT,
             USER_ID
      FROM TBL_PREPAID_DETAILS
      WHERE DATE_INSERT BETWEEN '01/01/2010' AND '14/11/2012'
      ORDER BY DATE_INSERT DESC)T2
   WHERE T2.USER_ID = A.USER_ID
     AND ROWNUM = 1) AS DATE_INSERT,

  (SELECT T3.PREV_BAL
   FROM
     (SELECT PREV_BAL,
             USER_ID
      FROM TBL_PREPAID_DETAILS
      WHERE DATE_INSERT BETWEEN '01/01/2010' AND '14/11/2012'
      ORDER BY PREPAID_DETAIL_ID ASC)T3
   WHERE T3.USER_ID = A.USER_ID
     AND ROWNUM = 1) AS DEPOSIT,

  (SELECT SUM(T4.CREDIT)
   FROM
     (SELECT CREDIT,
             USER_ID
      FROM TBL_PREPAID_DETAILS
      WHERE DATE_INSERT BETWEEN '01/01/2010' AND '14/11/2012'
      ORDER BY PREPAID_DETAIL_ID ASC)T4
   WHERE T4.USER_ID = A.USER_ID
     AND ROWNUM = 1) AS DEBIT,

  (SELECT SUM(T5.DEBIT + T5.PREV_BAL)
   FROM
     (SELECT DEBIT,
             PREV_BAL,
             USER_ID
      FROM TBL_PREPAID_DETAILS
      WHERE DATE_INSERT BETWEEN '01/01/2010' AND '14/11/2012'
      ORDER BY PREPAID_DETAIL_ID ASC)T5
   WHERE T5.USER_ID = A.USER_ID
     AND ROWNUM = 1) AS TOTAL_DEPOSIT
FROM TBL_USER A
LEFT JOIN TBL_PREPAID_DETAILS C ON A.USER_ID = C.USER_ID
LEFT JOIN TBL_ORGANIZATION_INFO B ON A.ORGANIZATION_ID = B.ORGANIZATION_ID
WHERE C.DATE_INSERT BETWEEN '01/01/2010' AND '14/11/2012'
  AND (A.USER_ID NOT IN ('xxx',
                         'xxx',
                         'xxx'))
GROUP BY A.FULLNAME,
         A.USER_ID,
         C.DATE_INSERT,
         B.NAME
ORDER BY A.FULLNAME;

Answer 1

Have a look at this page for general overview help on Oracle Tuning. Overall Oracle Tuning Page

Oracle provides a great deal of tools to tune performance, including what indexes could be added to improve a particular query. It is one of the first things I do when I encounter a slow running query. In your case, I would consider running an explain plan on your query and see what Oracle recommends. Here is the documentation on running an explain plan. Oracle Explain Plan