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Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio
...t the solution specifically for the "opencases" column be simpler as just "select count(1)..." (or "count" of any other literal)? The Where clause already specifies "and closed is NULL" so no need for summing a case statement in this instance. Also, I've heard (aeons ago) that "count(*)" is not as e...
What columns generally make good indexes?
...earching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such columns should be indexed against which yo...
get list of pandas dataframe columns based on data type
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If you are just selecting columns by data type, then this answer is obsolete. Use select_dtypes instead
– Ted Petrou
Nov 3 '17 at 16:58
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How do I get SUM function in MySQL to return '0' if no values are found?
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Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
The server principal is not able to access the database under the current security context in SQL Se
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DECLARE @UserName nvarchar(255)
DECLARE orphanuser_cur cursor for
SELECT UserName = su.name
FROM sysusers su
JOIN sys.server_principals sp ON sp.name = su.name
WHERE issqluser = 1 AND
(su.sid IS NOT NULL AND su.sid <> 0x0) AND
suser_sname(su....
Android Studio with Google Play Services
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Go to File -> Project Structure
Select 'Project Settings'
Select 'Dependencies' Tab
Click '+' and select '1.Library Dependencies'
Search for : com.google.android.gms:play-services
Select the latest version and click 'OK'
Voila! No need to fight with Grad...
Set selected index of an Android RadioGroup
Is there a way to set the selected index of a RadioGroup in android, other than looping through the child radiobuttons and selecting checking the radio button at the selected index?
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Finding median of list in Python
...t though: sorting is much more work in the worst case (Theta(n lg n)) than selecting the median (Theta(n))...
– Jeremy
Jun 11 '19 at 13:33
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How to determine total number of open/active connections in ms sql server 2005
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This shows the number of connections per each DB:
SELECT
DB_NAME(dbid) as DBName,
COUNT(dbid) as NumberOfConnections,
loginame as LoginName
FROM
sys.sysprocesses
WHERE
dbid > 0
GROUP BY
dbid, loginame
And this gives the total:
SELECT
CO...
querySelector search immediate children
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Though it's not a full answer, you should keep an eye on the W3C Selector API v.2 which is already available in most browser, both desktop and mobile, except IE (Edge seems to support): see full support list.
function(elem) {
return elem.querySelectorAll(':scope > someselector');
};
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