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    <p>While waiting for next Oracle 12c version, which supports <a href="http://docs.oracle.com/cd/E16655_01/appdev.121/e17620/adfns_design.htm#ADFNS967" rel="nofollow">Temporal Validity</a>, I still use next approach:</p> <pre><code>create table item ( title varchar2(32) primary key ); create table price ( price_id number primary key, item varchar2(32) not null references item (title), price number(9,2), effective_from date not null, effective_to date not null, effective_prev_to date, constraint price_from_to_ck check ( effective_to &gt; effective_from ), constraint price_to_prev_ck check ( effective_from = effective_prev_to + 1 ), constraint price_from_uq unique ( item, effective_to ), constraint price_dates_chain_fk foreign key ( item, effective_prev_to ) references price ( item, effective_to ) ); insert into item values ('LETTUCE'); insert into item values ('WHISKY'); insert into price values ( 1, 'LETTUCE', 1.05, date '2013-01-01', date '2013-03-31', null ); insert into price values ( 2, 'LETTUCE', 1.08, date '2013-04-01', date '2013-06-30', date '2013-03-31' ); insert into price values ( 3, 'WHISKY', 33.99, date '2013-01-01', date '2013-05-31', null ); insert into price values ( 4, 'WHISKY', 31.15, date '2013-06-01', date '2013-07-31', date '2013-05-31' ); </code></pre> <p>Let's <a href="http://sqlfiddle.com/#!4/e7df1/1" rel="nofollow">try</a>:</p> <pre><code>insert into price values ( 5, 'WHISKY', 30.55, date '2013-05-15', date '2013-06-05', date '2013-05-14' ); ORA-02291: integrity constraint (USER_4_E7DF1.PRICE_DATES_CHAIN_FK) violated - parent key not found : insert into price values ( 'WHISKY', 30.55, date '2013-05-15', date '2013-06-05', date '2013-05-14' ) </code></pre> <p>But now updating and deleting dates in the middle of the chain is pain in the ass. It needs to change preceding and following rows in one statement with <code>MERGE</code>. That's why I've added <code>price_id</code> column, because you can't update a key in <code>MERGE</code> -- so, you need another key instead of (item, effective_%).</p>
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    1. CO+1 for the 12c link. I'm taking a look at that possibility. The 12c concept of a "PERIOD" is very much the direction I want to go. I think it is entirely possible I could piece together something similar. Let me tinker and post what I come up with (for those of us in 11g for the foreseeable future).
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    2. COMy tinkering keeps leading me back to triggers. (sigh). This is far better a solution than a trigger in my opinion. And it isn't too cryptic. Also, wrapping a DAL around MERGE statements seems elegant enough. Thanks.
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    3. COJust FYI. Solution you provided in your question has two major lacks. First, **it doesn't work in concurrent environment**: one session see no changes that other sessions do until they commit it. Second, **it doesn't work immediatly**: when you _already_ have a broken data you need to insert something to make trigger to fire. Third, **it doesn't works at all**: you forgot to eliminate a row from `p` in subquery to `p2`, so you can insert just one row into the `price` table, then it will join to itself in `exists` part.
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