1. To insert data into a relation, we either specify a tuple, or write a query whose result is the set of tuples to be inserted. Attribute values for inserted tuples must be members of the attribute's domain.

2. An insertion is expressed by

r ← r ∪ E

where r is a relation and E is a relational algebra expression.

3. Some examples:

1. To insert a tuple for Smith who has $1200 in account 9372 at the SFU branch.

deposit ←deposit{("SFU", 9372, "Smith",1200)}

2. To provide all loan customers in the SFU branch with a $200 savings account.

r1←∑bname="SFU"(borrow))
r2 ←bname,loan#,cname(r1)
deposit deposit(r2×{(200)})