- I want to write the following query in SQL: Find cleaners (by name) who are not responsible for the model Daf. I could use the construct ‘Not In’. Which alternative construct could I also use in my query:
- Is Null
- Negative theta join
- Not Exists
- Exists
- The pair of SQL statements below is equivalent. True or false?
- True
- False
- The pair of SQL statements below is equivalent. True or false?
- True
- False
- Consider the following SQL query which uses a subquery to find cleaners by name who belong to the same depot as Vera
An alternative way of performing this query is:- an inner join
- an outer join
- a union
- a self join
- Listed below are the steps involved in executing a correlated query but they are out of order. What is the second step in the execution?
- Repeat until no candidate row remains.
- Whether or not the candidate row is retained depends on the values returned by the execution of the inner query.
- The inner query is executed, using the value from the candidate row fetched by the outer query.
- The outer query fetches a candidate row.
- We had two Student tables: one of students who are doing computing degrees; the other are students who speak Spanish. The __________ of the two tables would be students on computing degrees or who speak Spanish or both
- union
- intersection
- difference
- A programmer wrote the following code in SQL :
The purpose of this code is one of the following:- Find all those routes that James Bond can operate except for those routes that double-deckers can run on.
- Find all those routes that double-deckers can run on except for those routes operated by James Bond
- Find all those routes that double-deckers can run on or those routes operated by James Bond
- Find all those routes that double-deckers can run on and those routes operated by James Bond
- Consider the following SQL query which uses a subquery and the exists qualifier to list all cleaners who have been assigned to a depot.
The scope of a variable (or attribute) in SQL relates to where the attribute can be ‘seen’ in the query or subquery. Is the scope of the d.dNo within:- The whole query
- the outer select
- the inner select
- The relational algebra division operation allows us to compare two relations to see if one is a subset of the other.
What would be the result of the above operation? Is it:- 001
- 002
- 144
- Views are permanent tables in the database. True or false
- True
- False