Oracle SQL: Update a table with data from another table

Muhd picture Muhd · Aug 11, 2011 · Viewed 1M times · Source

Table 1:

id    name    desc
-----------------------
1     a       abc
2     b       def
3     c       adf

Table 2:

id    name    desc
-----------------------
1     x       123
2     y       345

In oracle SQL, how do I run an sql update query that can update Table 1 with Table 2's name and desc using the same id? So the end result I would get is

Table 1:

id    name    desc
-----------------------
1     x       123
2     y       345
3     c       adf

Question is taken from update one table with data from another, but specifically for oracle SQL.

Answer

Justin Cave picture Justin Cave · Aug 11, 2011

This is called a correlated update

UPDATE table1 t1
   SET (name, desc) = (SELECT t2.name, t2.desc
                         FROM table2 t2
                        WHERE t1.id = t2.id)
 WHERE EXISTS (
    SELECT 1
      FROM table2 t2
     WHERE t1.id = t2.id )

Assuming the join results in a key-preserved view, you could also

UPDATE (SELECT t1.id, 
               t1.name name1,
               t1.desc desc1,
               t2.name name2,
               t2.desc desc2
          FROM table1 t1,
               table2 t2
         WHERE t1.id = t2.id)
   SET name1 = name2,
       desc1 = desc2