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Category: MS SQL Development
HELP joining two tables

Hello,

I am creating a view that displays service codes and descriptions. I have two tables. Table 1 has service codes and table 2 has service code and description.

all of the fields in table 1 are dependant on table 2.

For example

Table 1

service_code1
service_code2
sevice_code3

Table 2

service_code
service_code_description

How can I join all three service codes from table 1 to table 2 to get each individual service code description?

service_code1
service_code_description1

service_code2
service_code_description2

service_code3
service_code_description3

how about you explain a little better and give us a few real values. Table one sounds completely erroneous if it's redundant in the primary key in table two.
this is what i'm pictureing


table 1 table 2
servcode servcode desc
123 123 blah
463 463 blah
987 967 blah


are certain descriptions missing where you have something in table 1 but nothing in table 2 and you want to know how to join these tables keeping the values in table 1 even though you have no entry in 2? Perhaps i just didn't understand your schema explanation....

Include the same description table three times. You can do this by using aliases, like this:

SELECT
a.Service_code1, b.Service_code_description,
a.Service_code2, c.Service_code_description,
a.Service_code3, d.Service_code_description
FROM table1 a, table2 b, table2 c, table2 d
WHERE
a.Service_code1=b.Service_code
AND a.Service_code2=c.Service_code
AND a.Service_code3=d.Service_code

-Dave

hmm,

table 1 contains three different service code fields.

exterior_service_code1 <--- contains 100 distinct codes
interior_service_code2 <--- contains 50 distinct codes
misc_service_code3 <--- contains 25 distinct codes

table 2 contains all of the descriptions for each code

service_code <--------contains all codes (exterior_service_code1, interior_service_code2 and misc_service_code3) <--- contains 175 distinct codes

serivice_description <-- contains 175 distinct descriptions

so the three fields get their description from table 2

does this help?

Originally posted by WineIsGood
Include the same description table three times. You can do this by using aliases, like this:

SELECT
a.Service_code1, b.Service_code_description,
a.Service_code2, c.Service_code_description,
a.Service_code3, d.Service_code_description
FROM table1 a, table2 b, table2 c, table2 d
WHERE
a.Service_code1=b.Service_code
AND a.Service_code2=c.Service_code
AND a.Service_code3=d.Service_code

-Dave

PERFECT! thanks Dave!










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