Fundementals Of Databases

Question 1

What do you always start a SQL query off with?

Answer 1

SELECT …
FROM …

Question 2

How would you begin to update a SQL query?(What statement)

Answer 2

UPDATE

Question 3

What is the equal to symbol in SQL

Answer 3

<>

Question 4

Explain the conditions under which simultaneous access to a database could cause a problem, and how this could be dealt with. (2 marks)

Answer 4

When 2 users try to modify the same record simultaneously.
Then you could either say this was dealt with…
- record locks - when a record is locked so a second user cannot modify the record if it is already being updated.
- transaction queuing - when updates are queued and the database software processes this in a FIFO order.