Oracle update multi-Table Association

Update A. A3 = A. A3 + B. B3

Table A structure: A1, A2, A3
Table B structure: B1, B2, B3
A1 and B1 are PK, and A1 = B1 can be used if the cut value is the same.

How can I implement the following functions using SQL statements or procedures ???

Update A3 of Table A with the sum of A. A3 and B. B3.

3> Update
Set a3 = (select a. A3 + B. B3 from B where a. A1 = B. B1 );

7> Update (select A1, A3, B1, B3 from a, B where a1 = b1) set a3 = A3 + B3

Opening an execution plan and talking about efficiency is meaningless .. The writing on the third floor is different from the writing on the seventh floor. The Writing Method on the third floor updates all records, while the Writing Method on the seventh floor only modifies the information related to the intersection of the two. The statement on the 7th floor can easily control the execution plan of the update statement, but table B must have a primary key index on the corresponding field :), if table B has a primary key index on the corresponding field, we recommend that you write the index on the 7th floor. Refer to this post ^_^. Http://www.cnoug.org/viewthread.php? Tid = 44070 (the test was not successful... I don't know how to do it) refer to the following: I admire it very much. With a learning attitude, I have rewritten the third floor. If there is no primary key, please advise: Update Set a3 = (select A3 + B3 from B where a1 = b1) Where a1 = (select B1 from B where a1 = b1): Update con_eme_on20050309 a set. con_price = (select. con_price + (B. annuity-a.annuity) +. nojob-a.nojob) +. medicare-a.medicare) +. birthfee-a.birthfee) +. bruisefee-a.bruisefee) from con_eme_on200404 B where. emp_cod = B. emp_cod and. if_act = '1' and. emp_base! = B. emp_base), A. emp_base = (select B. emp_base from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. annuity = (select B. annuity from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. nojob = (select B. nojob from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. Medicare = (select B. Medicare from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. birth1_= (select B. birth1_from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. bruisefee = (select B. bruisefee from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. nojobbase = (select B. nojobbase from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. mediabase = (select B. mediabase from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. birthbase = (select B. birthbase from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. bruisebase = (select B. bruisebase from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base) Where a. emp_cod in (select B. emp_cod from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base) Provident Fund: Update con_eme_on20050309 a set. con_price = (select. con_price + (B. accumulation-a.accumulation) from con_eme_on200404 B where. emp_cod = B. emp_cod and. if_act = '1' and. emp_base! = B. emp_base), A. Accumulation = (select B. accumulation from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. accumulationbase = (select B. accumulationbase from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base), A. accumulationbase1 = (select B. accumulationbase1 from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base) Where a. emp_cod in (select B. emp_cod from con_eme_on200404 B where a. emp_cod = B. emp_cod and A. if_act = '1' and A. emp_base! = B. emp_base)