Hellow everybody.
I have a problem difficult for me, please give me an advice.
I want to get a specific number of entry (rows) from a table
by each Key. If the number is 1, I can use select dinstinct,
but the number is not 1, I don't know how to select.
For example:
Key 0 | data 0-0
Key 0 |
A quick guess, or at least a starting point:
SELECT key, data
FROM myTable
GROUP BY key
LIMIT 2
HTH,
Arthur
On Sat, Dec 3, 2011 at 11:41 AM, Blog Tieng Viet blogtiengv...@yahoo.comwrote:
Hellow everybody.
I have a problem difficult for me, please give me an advice.
I want to get a
I'm having brain freeze, and wonder if anyone can help me with a query.
I have a library in MySQL. There's a table with a record per book, and other
tables that it indexes into for meaningful info. One of those is an
integer-keyed list of 1,000 Dewey Decimal Codes. In the books table, the Dewey
Second attempt, using a join, returns just one row for Dewey 000 with the
COUNT being about half the volumes in the library, which isn't right...
I thought a LEFT OUTER JOIN would have returned a record for every record in
s_library_dewey, but it only returns the first.
Brain freeze again...
On 12/3/2011 9:35 PM, Jan Steinman wrote:
Second attempt, using a join, returns just one row for Dewey 000 with the
COUNT being about half the volumes in the library, which isn't right...
I thought a LEFT OUTER JOIN would have returned a record for every record in
s_library_dewey, but it only
DOH! Brain unfroze, and I realized I needed an aggregate:
SELECT
COUNT(lib.Dewey) AS Have,
ddn.Dewey AS DDN,
ddn.Classification AS Classification
FROM s_library_dewey ddn
LEFT OUTER JOIN s_library lib ON ddn.Dewey = FLOOR(lib.Dewey)
WHERE 1
GROUP BY ddn.Dewey
... although if there
