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“Insert if not exists” statement in SQLite
... and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where text is equal to 'text to insert' and id is equal to 5, then the insert op...
How to delete an old/unused Data Model Version in Xcode
... model version were re-sorted improperly and the wrong default version was selected as I re-added the xcdatamodel file into the project. This may be because I am up to 38 model versions and I haven't changed the default version name, so the versions are named "MY_APP 37.xcdatamodel". I wanted to del...
How to stop a program running under Eclipse?
...r. For this you can open up the devices window (in the debug perspective), select the process and then press the stop button on the same window.
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How to remove a key from Hash and get the remaining hash in Ruby/Rails?
...m a hash and get the remaining hash in Ruby.
.slice => It will return selected keys and not delete them from the original hash. Use slice! if you want to remove the keys permanently else use simple slice.
2.2.2 :074 > hash = {"one"=>1, "two"=>2, "three"=>3}
=> {"one"=>1, "tw...
Long-lasting FB access-token for server to pull FB page info
...page admin)
Head over to the Facebook Graph API Explorer
On the top right, select the FB App you created from the "Application" drop down list
Click "Get Access Token"
Make sure you add the manage_pages permission
Convert this short-lived access token into a long-lived one by making this Graph API c...
Switching between GCC and Clang/LLVM using CMake
...sudo update-alternatives --config c++
Will print something like this:
Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/bin/g++ 20 auto mode
1 /usr/bin/clang++ 10 manual mode
2 ...
Get a list of distinct values in List
...
Notes.Select(x => x.Author).Distinct();
This will return a sequence (IEnumerable<string>) of Author values -- one per unique value.
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What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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Truncate (not round) decimal places in SQL Server
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select round(123.456, 2, 1)
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SQL Server Script to create a new user
...s using the Login you just declared:
Use YourDatabase;
GO
IF NOT EXISTS (SELECT * FROM sys.database_principals WHERE name = N'NewAdminName')
BEGIN
CREATE USER [NewAdminName] FOR LOGIN [NewAdminName]
EXEC sp_addrolemember N'db_owner', N'NewAdminName'
END;
GO
Now, Logins are a bit more flu...