• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 287
  • Last Modified:

A question about building SQL Query statement

I have a table(forecast), like below

value       element        description
--------------------------------------
26                    HI                 KM
20                    LO                 KM
SW                    D1                 KM
S                     D2                 KM
2                     F1                 KM
3                     F2                 KM
shower     WEATHER1       KM
shower     WEATHER2       KM
35                    HI                 GZ
25                    LO                 GZ
shower     WEATHER1       GZ
downfall   WEATHER2       GZ

I want to get the result below

CITY   WEATHER                      WIND       TEMPERATURE
-------------------------------------------------------------
KM     shower                     SW 2 to S 3     20-26
GZ     shower to downfall      N/A              25-35

(COMMENTS: If weather1=weather2 choose one, else join weather1 and weather2. The same as D1,F1 and D2, F2)

Could it be performed that only use the SQL Query statement?

And how to bulid SQL Query statement, if it can be done ?
0
Jerryleo
Asked:
Jerryleo
1 Solution
 
drittichCommented:
I recommend you change your columns in table forecast to:

DESCRIPTION
WEATHER1
WEATHER2
D1
F1
D2
F2
LO
HI


Then your select becomes extremely simple.  Otherwise you end up having to join the same table to itself nine times.
0
 
nycynikCommented:
what db are you using?  This is not possible in Access.

0
 
drittichCommented:
I wouldn't say it is not possible, just difficult.
0
What Kind of Coding Program is Right for You?

There are many ways to learn to code these days. From coding bootcamps like Flatiron School to online courses to totally free beginner resources. The best way to learn to code depends on many factors, but the most important one is you. See what course is best for you.

 
JerryleoAuthor Commented:
I use SQL Server 7
0
 
GibsonMDCommented:
Ok, here is what I have so far...  This only works if you have all the variables populated in the table.  Still a couple of things to work out with the display of the weather1 and weather2 value.

*****

SELECT Distinct Forecast.Descript AS city, Forecast.Value + ' - ' + forecast1.Value AS Temperature, forecast2.value + ' - ' + forecast3.value as Weather,
forecast4.Value + forecast5.value + ' to ' + forecast6.value + forecast7.value as Wind
FROM Forecast, forecast forecast1, forecast forecast2, forecast forecast3, forecast forecast4, forecast forecast5, forecast forecast6, forecast forecast7
WHERE (((forecast1.element = 'hi') AND (Forecast.element = 'lo')) and ((forecast2.element = 'weather1') and (forecast3.element = 'weather2'))) and  (((forecast4.element = 'd1') and (forecast5.element = 'f1')) and ((forecast6.element = 'd2') and (forecast7.element = 'f2')))
and forecast.descript = forecast1.descript and forecast.descript = forecast2.descript and forecast3.descript = forecast.descript and forecast.descript = forecast4.descript and forecast.descript = forecast5.descript and forecast.descript = forecast6.descript and forecast.descript = forecast7.descript
0
 
GibsonMDCommented:
Ok, here is what I have so far...  This only works if you have all the variables populated in the table.  Still a couple of things to work out with the display of the weather1 and weather2 value.

*****

SELECT Distinct Forecast.Descript AS city, Forecast.Value + ' - ' + forecast1.Value AS Temperature, forecast2.value + ' - ' + forecast3.value as Weather,
forecast4.Value + forecast5.value + ' to ' + forecast6.value + forecast7.value as Wind
FROM Forecast, forecast forecast1, forecast forecast2, forecast forecast3, forecast forecast4, forecast forecast5, forecast forecast6, forecast forecast7
WHERE (((forecast1.element = 'hi') AND (Forecast.element = 'lo')) and ((forecast2.element = 'weather1') and (forecast3.element = 'weather2'))) and  (((forecast4.element = 'd1') and (forecast5.element = 'f1')) and ((forecast6.element = 'd2') and (forecast7.element = 'f2')))
and forecast.descript = forecast1.descript and forecast.descript = forecast2.descript and forecast3.descript = forecast.descript and forecast.descript = forecast4.descript and forecast.descript = forecast5.descript and forecast.descript = forecast6.descript and forecast.descript = forecast7.descript
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

What Kind of Coding Program is Right for You?

There are many ways to learn to code these days. From coding bootcamps like Flatiron School to online courses to totally free beginner resources. The best way to learn to code depends on many factors, but the most important one is you. See what course is best for you.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now