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oracle sql key-preserved table. 在通过DML� �作Oracle的视图的时候,有一个很��的�� �是� �作的base表必� A table is key preserved if every key of the table can also be a key of the result of the join. Oracle 中用一个表的 Oracle SQL 实用基础教程PPT  SQL SQL column rid clear. Oracle 11.2 reduces this query to the Oracle now has selected T2 as the key-preserved table which is fine since  Buy Beginning Oracle SQL (Expert s Voice in Oracle) by Lex de Haan, Daniel cannot delete from view without exactly one key-preserved table (page 276)   I m having some difficulty understanding exactly what key-preserved means when joining two tables I thought that the idea was that if a key in one table could  Both tables have primary keys defined and I thought that my join was uniquely identifying rows, ORA-01779 cannot modify a column which maps to a non key-preserved table . Oracle SQL - How do I update from an Outer Joined Table SQL By adding a constraint on table T we have a key preserved join and can Step by Step install Oracle on Linux and Automate the installation using Shell  Failed SQL stmt UPDATE PS ROLUSR AUD VW W SET OPRID 1 tables. In Oracle it is generally allowed to update a join but there are a few conditions the here is nice explanation on the topic of key-preserved tables  3.5.1 Key-Preserved Tables. A key-preserved table is the most important requirement for a join view to be modifiable.. Mastering Oracle SQL, 2nd Edition  I imported data dictionary into SQL data modeler and cannot found out how Table “T� was created in database without specifying primary key  No other conditions are necessary to make a table key-preserved. Of course SQL select emp.ename, emp.rowid, dept.dname, dept.rowid Create global temporary table working emps on commit preserve rows Temporary Table � Table � Oracle PL / SQL. SQL SQL create table emp( 2 emp id integer primary key 3 ,lastname varchar2(20) not null 4 ,firstname varchar2(15)  ORA-01779 cannot modify a column which maps to a non key-preserved table. SQL update EMP DEPT VW set DNAME Rnd where DEPTNO 20 of The Database · Oracle DBMS STATS Gather Statistics of Schema, Tables, Indexes 

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