大约有 15,000 项符合查询结果（耗时：0.0232秒） [XML]
Using LIMIT within GROUP BY to get N results per group?
...to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR |...
PHP method chaining?
...imed at creating a DSL. Ex: $foo->setBar(1)->setBaz(2) vs $table->select()->from('foo')->where('bar = 1')->order('ASC). The latter spans multiple objects.
– Gordon
Sep 16 '10 at 7:32
...
How to retrieve the current value of an oracle sequence without increment it?
...
SELECT last_number
FROM all_sequences
WHERE sequence_owner = '<sequence owner>'
AND sequence_name = '<sequence_name>';
You can get a variety of sequence metadata from user_sequences, all_sequences and dba_...
how do I query sql for a latest record date for each user
...
select t.username, t.date, t.value
from MyTable t
inner join (
select username, max(date) as MaxDate
from MyTable
group by username
) tm on t.username = tm.username and t.date = tm.MaxDate
...
How to randomly select an item from a list?
...ults, but depending on the start seed, it's not guaranteed. If you want to select n distinct random elements from a list lst, use random.sample(lst, n)
– Graham
Dec 23 '18 at 17:02
...
How can I pair socks from a pile efficiently?
...n't think you need a lookup table. A single linear pass over the socks can convert the socks to number vectors, making the mapping of "sock segment" to bucket trivial. The socks can be tied to the vectors with string so that you don't need another linear pass at the end.
– Poin...
When is it better to use String.Format vs string concatenation?
...ng etc. religiously. However, after reading your (old) article, I am now a convert. Thanks
– stevethethread
Jan 21 '14 at 14:42
3
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How to best display in Terminal a MySQL SELECT returning too many fields?
...
Terminate the query with \G in place of ;. For example:
SELECT * FROM sometable\G
This query displays the rows vertically, like this:
*************************** 1. row ***************************
Host: localhost
Db: mydatabase1
...
How to subtract 30 days from the current datetime in mysql?
...
SELECT * FROM table
WHERE exec_datetime BETWEEN DATE_SUB(NOW(), INTERVAL 30 DAY) AND NOW();
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-add
...
Linq: What is the difference between Select and Where
The Select and Where methods are available in Linq. What should every developer know about these two methods? For example: when to use one over the other, any advantages of using one over the other, etc.
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