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Difference between “read commited” and “repeatable read”
...nd consider you have a simple task like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any da...
How to Implement Custom Table View Section Headers and Footers with Storyboard
...that tapping the section header causes the first cell in the section to be selected.
As Paul Von points out, this is fixed by returning the cell's contentView instead of the whole cell.
However, as Hons points out, a long press on said section header will crash the app.
The solution is to remove...
SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
...
Finding duplicate rows in SQL Server
...abase of organizations, and there are many duplicate rows. I want to run a select statement to grab all of these and the amount of dupes, but also return the ids that are associated with each organization.
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Query grants for a table in postgres
...
I already found it:
SELECT grantee, privilege_type
FROM information_schema.role_table_grants
WHERE table_name='mytable'
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Fix code indentation in Xcode
...
Before Xcode 9 (for Xcode 9 see default shortcut below)
select text
right-click
there's a "Re-indent selection" item in popup menu
In XCode 4 there is one more step:
select text
right-click
Click on "Structure"
there's a "Re-indent selection" and other options in popup men...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
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Rails ActiveRecord date between
...ne day. The field is part of the standard timestamps, is created_at . The selected date is coming from a date_select .
11...
The name 'model' does not exist in current context in MVC3
...ew Folder to add the folders. I should have right-clicked the project and selected Add -> Area. Then Visual Studio would have taken care of setting the area up correctly.
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Clear form fields with jQuery
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A small tip: this selector won't select input elements that are relying on the implicit type=text, you must explicitly include the type=text on your markup. That may be obvious, but it wasn't to me, just now :-)
– Elbin
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