Sarpras,
I assume your talking about mySql here. Entries in a SQL table (or "rows" in SQL-speak) is virtually unlimited - easily up into the millions. You can easily export/import SQL database from one host to another using the built-in mySql utilites - any geek could do this for you with little difficulty. Deleting rows/records/entries is a common task of SQL databases and is built-in as well.
Is there a specific application you are talking about here?