Command Other Than Append

[Drunkenneo]

We know when executing append query in a table if the query executed twice, then duplicate data get inserted,

Is there any other best solution to avoid such cases?

 

[Mihail]

1) To use indexes in order to not allow duplicates (the best I know)
2) To count records with sensible fields before running the update query

 

[Galaxiom]

If the data is coming from another table then use a query with an OUTER JOIN from the source table and the target table. An Is Null condition on a key field in the target table will prevent any existing records being repeated.

 

[RainLover]

If the data is coming from another table then use a query with an OUTER JOIN from the source table and the target table. An Is Null condition on a key field in the target table will prevent any existing records being repeated.

I prefer what Galaxiom suggested, It appears to be excessive to create an index just so that you can satisfy just one query.

 

[Galaxiom]

An Insert can also be simply adding a single record from a piece of constructed sql reading its values from a recordset or form.

In this case we would test for the presence of an existing record in the table. A DLookup is one way to do that.