大约有 47,000 项符合查询结果（耗时：0.0299秒） [XML]
How to calculate percentage with a SQL statement
...ultiplication of 100 in the wrong place and had some missing parenthesis.
Select Grade, (Count(Grade)* 100 / (Select Count(*) From MyTable)) as Score
From MyTable
Group By Grade
share
|
improve th...
Is it possible to specify condition in Count()?
...an use the fact that the count aggregate only counts the non-null values:
select count(case Position when 'Manager' then 1 else null end)
from ...
You can also use the sum aggregate in a similar way:
select sum(case Position when 'Manager' then 1 else 0 end)
from ...
...
Get record counts for all tables in MySQL database
...get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
19 Answers
...
Check if value is in select list with JQuery
...
Use the Attribute Equals Selector
var thevalue = 'foo';
var exists = 0 != $('#select-box option[value='+thevalue+']').length;
If the option's value was set via Javascript, that will not work. In this case we can do the following:
var exists = fal...
How can I confirm a database is Oracle & what version it is using SQL?
I'm building an installer for an application. The user gets to select a datasource they have configured and nominate what type of database it is. I want to confirm that the database type is indeed Oracle, and if possible, what version of Oracle they are running by sending a SQL statement to the dat...
Get top n records for each group of grouped results
...ould need to specify the group number and add queries for each group:
(
select *
from mytable
where `group` = 1
order by age desc
LIMIT 2
)
UNION ALL
(
select *
from mytable
where `group` = 2
order by age desc
LIMIT 2
)
There are a variety of ways to do this, see this articl...
jQuery to retrieve and set selected option value of html select element
I am attempting to retrieve and set the selected value of a select element (drop down list) with jQuery.
9 Answers
...
How can I generate an INSERT script for an existing SQL Server table that includes all stored rows?
...l need to run it at the database level.
Right-click the database in SSMS, select "Tasks", "Generate Scripts...". As you work through, you'll get to a "Scripting Options" section. Click on "Advanced", and in the list that pops up, where it says "Types of data to script", you've got the option to s...
How do you check what version of SQL Server for a database using TSQL?
...
Try
SELECT @@VERSION
or for SQL Server 2000 and above the following is easier to parse :)
SELECT SERVERPROPERTY('productversion')
, SERVERPROPERTY('productlevel')
, SERVERPROPERTY('edition')
From: http://support....
HTML Form: Select-Option vs Datalist-Option
I was wondering what the differences are between Select-Option and Datalist-Option. Is there any situation in which it would be better to use one or the other? An example of each follows:
...