Finding rows in a specific column of a given table
navi kumar
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Joined: May 10, 2006
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Hi,
I have a table named RECORD with columns( id varchar2(8), name varchar2(45), number NUMBER, category varchar2(45), file_content BLOB default=EMPTY_BLOB)
Each value in FILE_CONTENT field corresponds to specific value in CATEGORY field. Say for ex: file1 belongs to 'marketing' category.
Now I want retrieve the count of rows in file_content field basing on its corresponding category field value. There are 6 values allowed in the CATEGORY field.
One sol'n i find is to count the similar values in the CATEGORY field i.e, how many times 'marketing' is present and give the count of it. I dont understand how to write the code for this. Help me here.
The problem with the above sol'n is ..if a new value is added to the CATEGORY field, the code should be added in the application too!!! Please lemme know, if there are any alternatives!
PS1: Earlier, we were not having the CATEGORY field and the count for the entire table ws given. try { // Select the number of rows in the table Statement stmt = connection.createStatement(); ResultSet resultSet = stmt.executeQuery("SELECT COUNT(*) FROM RECORD");
// Get the number of rows from the result set resultSet.next(); int rowcount = resultSet.getInt(1); } catch (SQLException e) { }
PS2: APART from giving the count, i need to give the user a list of files(present in the FILE_content field) for each category. I mean to say, I need to give the user 6 lists( one for each category) with the corresponding files(BLOB in the FILE_CONTENT).
Any help is appreciated.
regards
Stan James
(instanceof Sidekick)
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Joined: Jan 29, 2003
Posts: 8791
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Look into the GROUP BY clause. I'm rusty but bet you could just add GROUP BY CATEGORY to your query and get what you're lookin for.
A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi
navi kumar
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Joined: May 10, 2006
Posts: 47
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Yes, We can upload the fields required using group by ...but how about giving the count of them??
stu derby
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Joined: Dec 15, 2005
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Originally posted by navi kumar: Yes, We can upload the fields required using group by ...but how about giving the count of them??
Count(*) works with a group by clause
I agree. Here's the link: http://ej-technologies/jprofiler - if it wasn't for jprofiler, we would need to
run our stuff on 16 servers instead of 3.
subject: Finding rows in a specific column of a given table