UPDATE Query with logic applied

Question

Hi Experts,
I need your help for now. Here is my requirement,
BANNER                                                                         
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - Production         
PL/SQL Release 11.1.0.7.0 - Production                                         
CORE     11.1.0.7.0     Production                                                     
TNS for 32-bit Windows: Version 11.1.0.7.0 - Production                        
NLSRTL Version 11.1.0.7.0 - Production                                         
5 rows selected.
DROP TABLE LINE_STATUS;
DROP TABLE LINE_CHILD;
CREATE TABLE LINE_STATUS
    LINE_ID     INTEGER     NOT NULL PRIMARY KEY,
    LINE_AMT    FLOAT,
    LINE_FLAG   INTEGER
INSERT INTO LINE_STATUS VALUES(1,1.52,0);
INSERT INTO LINE_STATUS VALUES(2,1.06,0);
INSERT INTO LINE_STATUS VALUES(3,2.05,0);
CREATE TABLE LINE_CHILD
    LINECHILD_ID        INTEGER NOT NULL PRIMARY KEY,
    LINECHILD_LINEID    INTEGER NOT NULL,
    LINECHILD_AMT       FLOAT
INSERT INTO LINE_CHILD VALUES (100,1,0.50);
INSERT INTO LINE_CHILD VALUES (101,1,0.50);
INSERT INTO LINE_CHILD VALUES (102,2,1.00);
INSERT INTO LINE_CHILD VALUES (103,2,0.05);NOW I NEED TO COLLECT THE SUM OF LINECHILD_AMT FOR EVERY LINECHILD_LINEID REFER LINE_STATUS(LINE_ID) AND TO CHECK
THE VALUES ARE SAME, THERE CAN BE DIFFERENCE 0.01 THEN TO UPDATE LINE_STATUS(LINE_FLAG) VALUE.
For Example:
SELECT SUM(LINECHILD_AMT) FROM LINE_CHILD WHERE LINECHILD_LINEID=1
Result is 1,
CASE
    WHEN LINE_STATUS(LINE_AMT)!=SUM(LINECHILD_AMT) THEN 2
    WHEN LINE_STATUS(LINE_AMT) =(LINE_STATUS(LINE_AMT)<=-0.01 OR LINE_STATUS(LINE_AMT)>=0.01 THEN 1
END CASE <<RESULT>>UPDATE LINE_STATUS,LINE_CHILD SET LINE_FLAG = CASE <<RESULT>> WHERE LINECHILD_LINEID= LINE_ID;
How can i achieve this ?
Thanks,

Answer 1

This may not be the exact requirement as per as values of CASE statement is concern, but it should serve your purpose.
SQL> select * from LINE_STATUS;
   LINE_ID   LINE_AMT  LINE_FLAG
         1       1.52          0
         2       1.06          0
         3       2.05          0
SQL> SELECT * FROM  LINE_CHILD;
LINECHILD_ID LINECHILD_LINEID LINECHILD_AMT
         100                1            .5
         101                1            .5
         102                2             1
         103                2           .05
SQL> ed
Wrote file afiedt.buf
  1  UPDATE LINE_STATUS
  2  SET LINE_FLAG=( WITH Sum_Line_Status AS ( SELECT LINE_ID S_LINE_ID,SUM(LINE_AMT) LINE_AMT_SUM
  3                                            FROM LINE_STATUS
  4                                            GROUP BY LINE_ID
  5                                          )
  6                  ,Sum_LINE_CHILD AS ( SELECT LINECHILD_LINEID S_LINECHILD_LINEID,
  7                                       SUM(LINECHILD_AMT) LINECHILD_AMT_SUM
  8                                       FROM LINE_CHILD
  9                                       GROUP BY  LINECHILD_LINEID
10                                     )
11                    SELECT
12                       CASE WHEN ABS(LINE_AMT_SUM-LINECHILD_AMT_SUM)>0.01 THEN 2
13                            WHEN LINE_AMT_SUM=LINECHILD_AMT_SUM THEN 1
14                            WHEN ABS(LINE_AMT_SUM-LINECHILD_AMT_SUM)<=0.01 THEN 3
15                       END
16                    FROM   Sum_Line_Status,Sum_LINE_CHILD
17                    WHERE  S_LINE_ID=S_LINECHILD_LINEID
18                    AND  S_LINE_ID=LINE_ID
19*                   )
20  /
3 rows updated.
SQL> SELECT * FROM  LINE_STATUS;
   LINE_ID   LINE_AMT  LINE_FLAG
         1       1.52          2
         2       1.06          3
         3       2.05