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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
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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...
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...
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
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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 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...
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...
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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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....
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
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