Beginner - 3 tables in 3 loops
I hope u need data for all tables.
1) You can go thru all tables and data with 1 loop if you do join all tables
in 1 singel select.
2) If the select is manually written it can be like this:
SELECT *
FROM YEAR,
PLANT,
GENERATOR
WHERE PLANT.FK = YEAR PK
AND GENERATOR FK = PLANT.PK
PK = Primary key, FK = foriegn key
You will have 1 row for each unik kombination.
"dsasorin" skrev:
Hi !
I am a beginner to databeses, and particulary to MS Access 2003. (althought I
passed the first lessons)
I want to make a small database with possibility to grow up. (max. 100
entries for a table)
I think that in my case the data must be structured like loop into loop.
Like that:
Year:
2000
2001
2002
2003
etc.
Plant:
plant_1
plant_2
plant_3
etc.
Generator:
gen_1
gen_2
gen_3
etc.
So for every Year it must exist some Power Plants, and for every Power Plant
it must exist some Generators.
I already have made 3 tables: YEAR, PLANT, GENERATOR with data in it.
So, few questions arise:
1. Is my algorithm any good (to consider 3 loops one in another for database)
?
2. If my algorithm is good, how should it be done the relationship between
tables ?
That is for start. Later i must make queries, input data, some logical
comparison, etc.
So i must do right from the beginning. I admit that my database must be done
for 8 loops, not 3, but if i understand for 3, the same it will be for 8.
Thanks in advance for help !
.
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