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How to round an average to 2 decimal places in PostgreSQL?
...old syntax for casting,
SELECT ROUND(AVG(some_column)::numeric,2)
FROM table;
works with any version of PostgreSQL.
There are a lack of overloads in some PostgreSQL functions, why (???): I think "it is a lack" (!), but @CraigRinger, @Catcall and the PostgreSQL team agree about "pg's historic r...
How to use pull to refresh in Swift?
...ddTarget(self, action: #selector(self.refresh(_:)), for: .valueChanged)
tableView.addSubview(refreshControl) // not required when using UITableViewController
}
@objc func refresh(_ sender: AnyObject) {
// Code to refresh table view
}
At some point you could end refreshing.
refreshControl...
Calling a function of a module by using its name (a string)
...["myfunction"]()
locals returns a dictionary with a current local symbol table. globals returns a dictionary with global symbol table.
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What is data oriented design?
...gner will also likely split out infrequently accessed data into a separate table rather than creating a table with huge number of columns were only a few of the columns are ever used. He might also choose to denormalize some of the tables so that data don't have to be accessed from multiple location...
How to get disk capacity and free space of remote computer
...omputers (input from the PowerShell pipeline) and displays the output in a table format with numeric values in human-readable form:
PS> $cred = Get-Credential -Credential 'example\administrator'
PS> 'db01','dc01','sp01' | Get-DiskFree -Credential $cred -Format | Format-Table -GroupBy Name -Au...
What is the proper way to re-attach detached objects in Hibernate?
...nate Session (a.k.a Persistence Context) and is not mapped to any database table row is considered to be in the New (Transient) state.
To become persisted we need to either explicitly call the EntityManager#persist method or make use of the transitive persistence mechanism.
Persistent (Managed)
...
Which HTML elements can receive focus?
...ment, HTMLSelectElement, HTMLTextAreaElement and HTMLAnchorElement. This notably omits HTMLButtonElement and HTMLAreaElement.
Today's browsers define focus() on HTMLElement, but an element won't actually take focus unless it's one of:
HTMLAnchorElement/HTMLAreaElement with an href
HTMLInputElement/...
Is there a point to minifying PHP?
...o improve performance... after performing benchmarking and profiling and establishing that caching itself will be the best possible performance gain.
– Charles
Nov 2 '10 at 16:58
1...
There is no ViewData item of type 'IEnumerable' that has the key 'xxx'
...e is the source SelectList.
What happened with my error was:
Because the table containing the drop down lists was in a partial view and the ViewData had been changed and no longer contained the SelectList I had referenced, the HtmlHelper (instead of throwing an error) tried to find the SelectList...
Getting the closest string match
...o far.
While unused in the final optimization, a benchmarking sheet was established which matches columns to themselves for all perfect results down the diagonal, and lets the user change parameters to control the rate at which scores diverge from 0, and note innate similarities between search phra...