sql data save query

Question

I want to save new data from access tables to sql tables without overwriting old data in sql. Data table format for access and sql is same.(using Visual Basic)

Answer 1

If there is a unique id on the row, then you can check whether the value is already in the database (logically equivalent to this):

insert into data_table dt
select * from access_table a
where a.id not in (select id from data_table)

A unique id, of course, is any subset of fields in the row, identifying a unique row.