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Update MongoDB field using value of another field
...ion 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 also introduced the $set pipeline stage operator which is an...
MySQL integer field is returned as string in PHP
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I just did some tests on Windows with Laravel and Mysql on the very same schema and database server. On Windows the primary key is returned as an Integer and on Linux it's a String.
– AturSams
Oct 28 '14 at 15:38
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How do I set up a simple delegate to communicate between two view controllers?
I have two UITableViewControllers and need to pass the value from the child view controller to the parent using a delegate. I know what delegates are and just wanted to see a simple to follow example.
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Formula px to dp, dp to px android
...ing to calculate a variable amount of pixels to density independent pixels and vice-versa.
20 Answers
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Rails: confused about syntax for passing locals to partials
Understanding Rails "magic" with regards to rendering partials (and passing locals into them).
4 Answers
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SQL - using alias in Group By
...d because they must have been introduced in a previous step.
So in Oracle and SQL Server, you cannot use a term in the GROUP BY clause that you define in the SELECT clause because the GROUP BY is executed before the SELECT clause.
There are exceptions though: MySQL and Postgres seem to have additi...
Can't launch my app in Instruments: At least one target failed to launch
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Edit the scheme for your target and under "Profile [App Name]" set the Build Configuration to Debug (it's usually Release by default).
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Programmatically select text in a contenteditable HTML element?
... input or textarea element. You can focus an input with ipt.focus() , and then select its contents with ipt.select() . You can even select a specific range with ipt.setSelectionRange(from,to) .
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What is the behavior of integer division?
...ion? What is the defined behavior?
Yes, integer quotient of the two operands.
6.5.5 Multiplicative operators
6 When integers are divided, the result of the / operator is the algebraic quotient with any
fractional part discarded.88) If the quotient a/b is representable, the expression
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SQL select only rows with max value on a column [duplicate]
...ou join your table to the sub-query with equality on both group-identifier and max-value-in-group:
SELECT a.id, a.rev, a.contents
FROM YourTable a
INNER JOIN (
SELECT id, MAX(rev) rev
FROM YourTable
GROUP BY id
) b ON a.id = b.id AND a.rev = b.rev
Left Joining with self, tweaking join...