仅将选择的值从一个表复制到另一个表，并附带条件

Question

I am trying to copy selected values from rows of one table to another table, the problem is that SQLite gives an error for a nested SELECT command as

java.sql.SQLException: only a single result allowed for a SELECT that is part of an expression

Here is what I am trying:

INSERT INTO table2(ID, ProjectName ) 
SELECT ID, ProjectName FROM table1
Where table1.ID NOT IN table2

I can't use * here, since table1 has four columns and table2 has only 3. All has to be done is to check if any ID value from table1 is not present in table2 , then copy only that ID , respective ProjectName values from table1 and insert it into table2 as ID, ProjectName , null

null is for the thrid column value in table2.

Any suggestions or help would be great

Answer 1

Your query is almost there:

INSERT INTO table2(ID, ProjectName ) 
    SELECT ID, ProjectName
    FROM table1
    Where table1.ID NOT IN (select table2.id from table2);

This is standard SQL, so it should work in any database.