Database 1
Data Manipulation
- Prof. dr. Paul M.E. De Bra
- Dept. of Computer Science
- Eindhoven Univ. of Technology
Recognizing Types of Queries
- Identify the type of the following queries, and afterwards also translate them to the algebra (PSJ, union, intersection, difference, division):
- Give the name of customers that have a loan with a branch where they also have an account.
- Give the name of customers who have a loan at a branch where they do not have an account.
- Give the name of customers who have a loan at every branch where they have an account.
- Give the name of customers who have loans only at branches where they have an account.
Reading Queries
- {customer-name}(balance>amount(account depositor borrower loan))
- {branch-name}(branch) {branch-name}(branch-city customer-city(branch account depositor customer))
- {X.customer-name} (X.account-number = Y.account-number X.customer-name Y.customer-name (X(depositor) Y(depositor)))
Preparation for labsession 2
- Study section 3.6 of the database book.
- This section deals with the tuple calculus, a declarative query language similar to logic expressions.
- In the labsession we are going to try formulating queries in the tuple calculus, and reading them back.