Beginning SQL

To demonstrate the sort of results RAND() gives, execute the following SQL:
SELECT MemberId, MemberId + RAND(), RAND() FROM MemberDetails
ORDER BY MemberId;
The code returns MemberId, MemberId plus a random number, and finally a random number that the
database system generates on its own.
The query produces 13 results, one for each record in the table:
MemberId MemberId + RAND() RAND()
1 1.133239 0.142173
4 4.311148 0.129218
5 5.712648 0.175588
6 6.739993 0.173202
7 7.64603 0.710545
8 8.614636 0.941545
9 9.863819 0.494457
10 10.88083 0.920768
11 11.96136 0.044484
12 12.33835 0.558281
13 13.77636 0.206976
14 14.70579 0.908012
15 15.4227 0.389447
Because it’s random, your results will be different from the ones shown here. Note that in MS SQL
Server, the RAND() function generates the fractional part, and it also generates only one random number
for each RAND() used in a results set. Most databases (IBM’s DB2, for example) create a new random
number for each record. Such long fractional numbers are not really that useful, but you can make them
whole numbers by multiplying them and then using one of the rounding functions (discussed in the
next section) to cut off the fractional part.
Rounding Numbers
Manipulating Data
The final three math functions covered here are all related, the relationship being that they all remove all
or part of the fractional part of a floating-point number. The difference among the three is how they
decide to remove the part after the decimal point. The three rounding functions are CEILING(), FLOOR(),
and ROUND(), each covered in its own section.
Before continuing with the discussion of the rounding functions, you need to add some data to the
Film Club database. In addition to keeping track of whether a film is available on DVD, the film club
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