|
It sure is possible, you just need to watch out for what happens if either field is NULL, and also be aware that "A" is not the same as "a" so you might want to force to upper case, of course, this might not be an issue depending on your constraints when entering the results.
-------------------------------------------
Damian - Insert snappy one-liner here.
|
|
|
|
|
Try comparing ASCII values of the characters
Regards
KP
|
|
|
|
|
Hi all,
I'm trying to create a "generic" hierarchical model to store simple parent/child relationships. The closest approximation to what I'm trying to end up with is strongly based on the file system model. In SQL, I've defined the following table:
- ID (auto-generated, unique, non-nullable)
- NAME (just a string to be displayed to the user)
- PARENT_ID
The one fundamental constraint above all others I want to enforce at the database level is that any PARENT_ID value, if it has a non-NULL value at all, must exist somewhere in the ID field in this table. There are other restrictions that would be nice to have, but I can live with having this one only as a starting point.
Ultimately, I want to be able to store something like this:
C:\TEST1\FOLDER1
C:\TEST1\FOLDER2
C:\TEST1\FOLDER2\SUBFOLDER1
C:\TEST2\FOLDER1
...as:
1, "TEST1", NULL
2, "FOLDER1", 1
3, "FOLDER2", 1
4, "SUBFOLDER1", 3
5, "TEST2", NULL
6, "FOLDER1", 5
For some reason, suggesting this sort of thing in primarily SQL-oriented newsgroups seems to make the natives want to break out the tar and feathers...I'm apparently "thinking too much like an older developer used to linked lists and pointers". Fine, maybe I can't see the forest for the trees, but this "simple" model (in my eyes), if I can get it to work, would provide me with all the flexibility I need.
Ultimately, I'm NOT interested in writing any convoluted recursive queries to walk back up the PARENT_ID chain for a given node/row. The most complicated thing I might do is draw a tree (in ASP.NET), starting at the top level only (listing those entries whose PARENT_ID is NULL), and fetch a node's children when that node is clicked (select those entries whose PARENT_ID matches the ID of the node clicked).
Is this approach going to work, or do I have to scrap this entirely and put myself through hundreds of pages of data modeling theory, as the SQL gurus elsewhere seem to be suggesting?
If this is workable, could some kind soul *please* show me a SQL script to create this table with the appropriate constraints in place--or at least tell me what to click in SQL Server 2005 Management Studio to establish the constraints. I can't figure that part out (defining the table is easy, it's defining the "must exist in the ID column" rule for the PARENT_ID column I'm struggling with).
I'll save the "what's with the animosity among SQL developers towards old-fashioned software developers" question for another thread...
|
|
|
|
|
Pretty UIs to click through be damned. I managed to define my table as:
CREATE TABLE CATEGORIES
(
CAT_ID int IDENTITY(1,1) NOT NULL,
PARENT_ID int NULL,
CAT_NAME VARCHAR(50) NOT NULL,
PRIMARY KEY(CAT_ID),
FOREIGN KEY(PARENT_ID)REFERENCES CATEGORIES (CAT_ID)
)
Thoughts welcomed anyway.
|
|
|
|
|
I am trying to retrieve random rows from a database that I have in access. I got the sql statement to give me the database in random order, but I want to retrieve only 3 random rows from the database. THis is what I have so far:
SELECT *
FROM Jurors
ORDER BY rnd();
Please Help
Thank you
Steve Vondras
Red Lake Nation
MIS Tech
svondras@redlakenation.org
|
|
|
|
|
Describe the Jurors table in terms of the fields that are used. Not describing the how the table is set up, isn't going to allow anyone to really help you.
"That's no moon, it's a space station." - Obi-wan Kenobi
|
|
|
|
|
The jurors table has only two fields and I want both to appear. THere are about 20 different jurors, and I want to be able to randomly select 2 of them.
Steve Vondras
Red Lake Nation
MIS Tech
svondras@redlakenation.org
|
|
|
|
|
What are the two fields? Are you trying to do all of this from within Access or do you have an app tied into the database?
"Any sort of work in VB6 is bound to provide several WTF moments." - Christian Graus
|
|
|
|
|
The two fields are FIRST and LAST name, and I am doing this from within access.
Steve Vondras
Red Lake Nation
MIS Tech
svondras@redlakenation.org
|
|
|
|
|
You should have an id field that is a primary key. You can query by the id field with the randomly generated number.
"Any sort of work in VB6 is bound to provide several WTF moments." - Christian Graus
|
|
|
|
|
if you are able to get random row.then why don't you pick TOP 3 rows from the output
|
|
|
|
|
Where do I put TOP 3 in at on this statement:
SELECT *
FROM jurors
ORDER BY rnd();
I am very new sql thank you for your help
Steve Vondras
Red Lake Nation
MIS Tech
svondras@redlakenation.org
|
|
|
|
|
Replace the * with TOP 3...
"Any sort of work in VB6 is bound to provide several WTF moments." - Christian Graus
|
|
|
|
|
Thank you for the help.
Steve Vondras
Red Lake Nation
MIS Tech
svondras@redlakenation.org
|
|
|
|
|
No problem, Steve.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
|
|
|
|
|
Hi all!
I've a SQL (2005) database that is structured as follows:
- a schema called "salary"
- the table name is given by the year and the effective table name. Example 2007.employees
- that gives the table name salary.[2007.employees]
In my project I've created a typed dataset with the wizard. I've then renamed the table name in the dataset without the year (ex. 2007.employees -> employees).
In the application I can choose in which year to work and should load the data from the choosen year in the dataset. I should have the possibiltiy to pass to the tabeladapter the year I want. How can I do that?
Thanks for suggestions!
Jörg
|
|
|
|
|
I think you look in the properties of the data adapter and include parameters.
"Any sort of work in VB6 is bound to provide several WTF moments." - Christian Graus
|
|
|
|
|
Yes it's possible the add parameters in the table adapter, but not for the table names. When you try to add a paramter for the table name, the query builder gives an error.
I'm now thinking to add a column "Year" in each table, so that each row is allocated in a year and all data is in one table and database.
|
|
|
|
|
Hello
How can I cancel inner join between two tables if the value in second table not exists ..
to be more clear
TableA
-Col1
-Col2
-Col3
TableB
-Col1
-Col2
-Col3
-Col9
select TableA.col1 ,TableA.col2 ,TableB.Col1
where TableA.col3=TableB.Col9
the result will diplay if the match happend I have tried to do like this
in
TableA.col3=isNull(TableB.Col9,TableA.col3)
or something like that..
the problem that I face in sqlDataSource in asp.net
aj123
|
|
|
|
|
I did not understand your question but i guess you are looking for: 'coalesce' - try this out
Gautham
|
|
|
|
|
Use the INNER JOIN syntax.
SELECT a.Col1, a.Col2 FROM TableA a
INNER JOIN TableB b
ON b.FK_Field = a.PK_Field This will return you rows where items are present in both tables only.
|
|
|
|
|
Use a left join:
select TableA.col1 ,TableA.col2 ,TableB.Col1<br />
From TableA<br />
inner join TableB on TableA.col3=TableB.Col9
Wout Louwers
|
|
|
|
|
yes that right..
I forget that...
aj123
|
|
|
|
|
Hi
I stuck at an INSERT Query using two tables.
I have two tables Table1 and Table2.In Table1 I have 2 columns,one with dupicate value and another with null values.In Table2 I have 2 columns,both the columns have unique values.
Now I have to INSERT values from Table2 to Table1 with the corresponding or maching values like
Table1
StateCode StateName
--------- ----------
AK NULL
AK NULL
AK NULL
AL NULL
AL NULL
AL NULL
CO NULL
CO NULL
CO NULL
Table2
StateCode StateName
--------- ----------
AK Alaska
AL Alabama
AR Arkansas
AZ Arizona
CA California
CO Colorado
I have to INSERT values into Table1 in the null column from Table2 w.r.t StateCode.
Help me 
Suggest me an example.
I have not failed. I've just found 10,000 ways that won't work. -Thomas A. Edison
Thank u
Chandu
|
|
|
|
|
Hi Chandu
Sounds like you need to "update". Something like:
update Table1 set StateName = Table2.StateName
from Table2
where Table2.StateCode = Table1.StateCode Regards
Andy
If you want to thank me for my help, please vote my message by clicking one of numbers beside "Rate this message".
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
