Question

I have two tables with the same schemas, table A and table B:

| Table [A]        | Table [B]   
| id    value      | id    value
| 1     15         | 1     19
| 2     18         | 3     28
| 5     22         | 4     39

I would like to do:

insert into a select * from b where [b.id not exists in a]

Question: What’s the syntax for this – in particular, the portion in the brackets?

Answer 1

use INSERT INTO..SELECT statement and LEFT JOIN.

INSERT INTO tableB (id, Value)
SELECT  a.id, a.value
FROM    tableA a
        LEFT JOIN tableB b 
            ON a.ID = b.ID
WHERE   b.id IS NULL

• SQLFiddle Demo