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What is this operator in MySQL?
...d <> both give UNKNOWN with NULL on either side of the expression.)
SELECT *
FROM table
WHERE YourColumn IS NOT NULL;
can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
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Database Design for Tagging
... to rebuilt every time a question has a tag added or removed. A query like select * from question q inner join question_has_tag qt where tag_id in (select tag_id from tags where (what we want) minus select tag_id from tags where (what we don't) should be fine and scale out assuming the right b-tree ...
Code formatting shortcuts in Android Studio for Operation Systems
...System Settings → Keyboard → Shortcuts tab → System → Lock Screen.
Select the row New Accelerator..., then press any special key with the Alpha key (e.g. Shift + L). You should've successfully changed the keyboard shortcut.
Check if the keyboard shortcut now works in Android Studio.
Altern...
How do you open an SDF file (SQL Server Compact Edition)? [closed]
...t intuitive:
Open SQL Server Management Studio, or if it's running select File -> Connect Object Explorer...
In the Connect to Server dialog change Server type to SQL Server Compact Edition
From the Database file dropdown select < Browse for more...>
Open your SDF file.
...
How do I hide .class files from the Open Resource dialog in Eclipse?
...
Right click on the project and select Properties
Expand Resource and click on Resource Filters
Click on Add Filter... to create a new filter
On the dialog box that opens
Select the Exclude all and Files radio buttons
Under File and Folder Attributes e...
How to execute a bash command stored as a string with quotes and asterisk [duplicate]
...quotes.
MYSQL='mysql AMORE -u username -ppassword -h localhost -e'
QUERY="SELECT "'*'" FROM amoreconfig" ;# <-- "double"'single'"double"
eval $MYSQL "'$QUERY'"
Bonus: It also reads nice: eval mysql query ;-)
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Why can't radio buttons be “readonly”?
...ton by disabling only the un-checked radio buttons. It keeps the user from selecting a different value, and the checked value will always post on submit.
Using jQuery to make readonly:
$(':radio:not(:checked)').attr('disabled', true);
This approach also worked for making a select list readonly, ...
Replace duplicate spaces with a single space in T-SQL
...
Even tidier:
select string = replace(replace(replace(' select single spaces',' ','<>'),'><',''),'<>',' ')
Output:
select single spaces
...
Use LINQ to get items in one List, that are not in another List
...erride the equality:
var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));
This variant does not remove duplicates.
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Select records from NOW() -1 Day
... by >= NOW() -1 so all records from the day before today to the future are selected?
6 Answers
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