大约有 43,000 项符合查询结果（耗时：0.0272秒） [XML]
Can I set an unlimited length for maxJsonLength in web.config?
...retrieve the list of more then 17000 records (each won't have more than 10 char length), it's exceeding the length and throws the error:
...
How can I view all the git repositories on my machine?
...ameter cannot be found that matches parameter name 'Attributes'. At line:1 char:28
– Dewald Swanepoel
Jan 30 '17 at 9:33
...
Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
...
Get top 1 row of each group
...
;WITH cte AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC) AS rn
FROM DocumentStatusLogs
)
SELECT *
FROM cte
WHERE rn = 1
If you expect 2 entries per day, then this will arbitrarily pick one...
Oracle SQL Query for listing all Schemas in a DB
...
Using sqlplus
sqlplus / as sysdba
run:
SELECT *
FROM dba_users
Should you only want the usernames do the following:
SELECT username
FROM dba_users
share
|
...
Return rows in random order [duplicate]
...
SELECT * FROM table
ORDER BY NEWID()
share
|
improve this answer
|
follow
|
...
Difference between Select and ConvertAll in C#
...
Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You s...
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
...
Trigger change event using jquery
is there anyway i could trigger a change event on select box on page load and select a particular option.
8 Answers
...
Counting null and non-null values in a single query
...le and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us;
...