ibm informix ids merge語句為dml語句，用來對比兩個表的記錄情況，根據情況執行insert的同時執行update或者delete操作。
ids11.5xc6及以上版本支援該功能
1.表sale為目標表，new_sale為**表，通過cust_id對比兩個表的資料，當sale表有與new_sale相同的記錄時，執行update更新sale表的salecount屬性，當sale表中沒有new_sale中相應的記錄，則把該記錄insert 到sale表中
merge into sale using new_sale as n
on sale.cust_id = n.cust_id
when matched then update
set sale.salecount = sale.salecount + n.salecount
when not matched then insert (cust_id, salecount)
values (n.cust_id, n.salecount);
2.merge into customer c
using ext_customer e
on c.customer_num=e.customer_num
when matched then
update set c.fname = e.fname,
c.lname = e.lname,
c.company = e.company,
c.address1 = e.address1,
c.address2 = e.address2,
c.city = e.city,
c.state = e.state,
c.zipcode = e.zipcode,
c.phone = e.phone
when not matched then
insert (c.fname, c.lname, c.company, c.address1, c.address2,
c.city, c.state, c.zipcode, c.phone)
values
(e.fname, e.lname, e.company, e.address1, e.address2,
e.city, e.state, e.zipcode, e.phone);
3.merge into customer c
using ext_customer e
on c.customer_num=e.customer_num
and c.fname=e.fname and c.lname=e.lname
when matched then
update set c.fname = e.fname,
c.lname = e.lname,
c.company = e.company,
c.address1 = e.address1,
c.address2 = e.address2,
c.city = e.city,
c.state = e.state,
c.zipcode = e.zipcode,
c.phone = e.phone
when not matched then
insert
(c.fname, c.lname, c.company, c.address1, c.address2,
c.city, c.state, c.zipcode, c.phone)
values
(e.fname, e.lname, e.company, e.address1, e.address2,
e.city, e.state, e.zipcode, e.phone);
4.merge into customer c
using ext_customer e
on c.customer_num=e.customer_num
when matched then
update set c.fname = e.fname,
c.lname = e.lname,
c.company = e.company,
c.address1 = e.address1,
c.address2 = e.address2,
c.city = e.city,
c.state = e.state,
c.zipcode = e.zipcode,
c.phone = e.phone ;
5.merge into customer c
using ext_customer e
on c.customer_num=e.customer_num
when matched then
delete ;
6.merge into customer c
using ext_customer e
on c.customer_num=e.customer_num and c.fname=e.fname
and c.lname=e.lname
when not matched then
insert
(c.fname, c.lname, c.company, c.address1, c.address2,
c.city, c.state, c.zipcode, c.phone)
values
(e.fname, e.lname, e.company, e.address1, e.address2,
e.city, e.state, e.zipcode, e.phone);
7.merge into customer c
using ext_customer e
on c.customer_num=e.customer_num and c.fname=e.fname and c.lname=e.lname
when not matched then
insert
(c.fname, c.lname, c.company, c.address1, c.address2,
c.city, c.state, c.zipcode, c.phone)
values
(e.fname, e.lname, e.company, e.address1, e.address2,
e.city, e.state, e.zipcode, e.phone)
when matched then update
set c.fname = e.fname,
c.lname = e.lname,
c.company = e.company,
c.address1 = e.address1,
c.address2 = e.address2,
c.city = e.city,
c.state = e.state,
c.zipcode = e.zipcode,
c.phone = e.phone ;
8.merge into customer c
using (select * from ext_customer e1, orders e2
where e1.customer_num=e2.customer_num ) e
on c.customer_num=e.customer_num and c.fname=e.fname
and c.lname=e.lname
when not matched then
insert (c.fname, c.lname, c.company, c.address1, c.address2,
c.city, c.state, c.zipcode, c.phone)
values (e.fname, e.lname, e.company, e.address1, e.address2,
e.city, e.state, e.zipcode, e.phone)
when matched then
update set c.fname = e.fname,
c.lname = e.lname,
c.company = e.company,
c.address1 = e.address1,
c.address2 = e.address2,
c.city = e.city,
c.state = e.state,
c.zipcode = e.zipcode,
c.phone = e.phone ;
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