Update values of one table from other table - sql

Question

For Example I have 2 tables
Table 1:
id number name
-----------------------
1 1684 abc
2 9666 pqr
3 1234 adf
Table 2:
id number name
-----------------------
1 9109 xyz
2 9564 pqr
How do i get output like this?
Table 1:
id number name
-----------------------
1 9109 xyz
2 9564 pqr
3 1234 adf
I want to merge table 2 in table.
Also if the column-"name" value is updated/changed from this merge, I need to update status column and i need to call a procedure of smtp mail, how can i handle this?
The status column has different status transitions(eg: x->y, a->b).
and if the record is not in table1 it should be inserted.
These all operations are inside a procedure used in batch job.
Please advice me with this.
Thank you in advance for help.

Answer 1

There are different ways to do this, say, using MERGE statement, but most simple is
Connected to Oracle Database 12c Enterprise Edition Release 12.1.0.2.0
SQL> create table t$1 ("id" integer, "number" integer, "name" varchar2(3));
Table created
SQL> create table t$2 ("id" integer, "number" integer, "name" varchar2(3));
Table created
SQL> insert into t$1 values (1, 1684, 'abc');
1 row inserted
SQL> insert into t$1 values (2, 9666, 'pqr');
1 row inserted
SQL> insert into t$1 values (3, 1234, 'adf');
1 row inserted
SQL> insert into t$2 values (1, 9109, 'xyz');
1 row inserted
SQL> insert into t$2 values (2, 9564, 'pqr');
1 row inserted
SQL> update t$1 set
2 ("number", "name") = (select "number", "name" from t$2 where t$2."id" = t$1."id")
3 where
4 "id" in (select "id" from t$2);
2 rows updated
SQL> select * from t$1;
id number name
-------- -------- --------
1 9109 xyz
2 9564 pqr
3 1234 adf

Answer 2

You can use MERGE to do it very simply:
MERGE INTO table1 dst
USING table2 src
ON ( src.id = dst.id )
WHEN MATCHED THEN
UPDATE SET number = src.number,
name = src.name;