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SQL JOIN help

I have two tables (simplified example):

table person
PK data
1 A
2 B
3 C
4 D

table choice
PK FK
1 1
2 1
3 1
4 2
5 2
6 2

I need to count the total number of people that made a choice. Each
person should only be counted once, regardless of how many choices they
have.

Thanks in advance for the help!

Jul 23 '05 #1
1 1003
provided that referential integrity holds between the two tables. (No choice
records for persons who dont exist)

SELECT Count(DISTINCT FK) FROM Choice

Mr Tea
<mi**********@hotmail.com> wrote in message
news:11**********************@f14g2000cwb.googlegr oups.com...
I have two tables (simplified example):

table person
PK data
1 A
2 B
3 C
4 D

table choice
PK FK
1 1
2 1
3 1
4 2
5 2
6 2

I need to count the total number of people that made a choice. Each
person should only be counted once, regardless of how many choices they
have.

Thanks in advance for the help!

Jul 23 '05 #2

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