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How do I force Postgres to use a particular index?
...d, client_id, date, and description. You want to run the following query:
SELECT client_id, SUM(amount)
FROM transactions
WHERE date >= 'yesterday'::timestamp AND date < 'today'::timestamp AND
description = 'Refund'
GROUP BY client_id
PostgreSQL may choose to use the index transaction...
Sublime Text 3, convert spaces to tabs
... And this does on the entire file, and can not be done only on a selection.
– not2qubit
Jan 8 '18 at 17:55
...
Natural Sort Order in C#
...haNumeric<T>(this IEnumerable<T> source, Func<T, string> selector)
{
int max = source
.SelectMany(i => Regex.Matches(selector(i), @"\d+").Cast<Match>().Select(m => (int?)m.Value.Length))
.Max() ?? 0;
return source.OrderBy(i => Regex.Replace(s...
Get the current displaying UIViewController on the screen in AppDelegate.m
...return [UIWindow getVisibleViewControllerFrom:[((UITabBarController *) vc) selectedViewController]];
} else {
if (vc.presentedViewController) {
return [UIWindow getVisibleViewControllerFrom:vc.presentedViewController];
} else {
return vc;
}
}
}...
mongodb group values by multiple fields
...urse the ability to interpolate the variable through $expr using $match to select the matching items in the "join", but the general premise is a "pipeline within a pipeline" where the inner content can be filtered by matches from the parent. Since they are both "pipelines" themselves we can $limit e...
Chrome DevTools Devices does not detect device when plugged in
...
Found it under Developer options > Select USB configuration. Changed it to "PTP (Picture Transfer Protocol)", but didn't solve the problem
– zok
Jul 5 '16 at 10:56
...
Checkout one file from Subversion
...ithin the repository containing all the files that you wish to work on and Select Checkout.
Step 3: Within new popup window, ensure that the checkout directory points to the correct location on your local PC. There will also be a dropdown menu labeled “checkout depth”. Choose “Only this item...
How does the main() method work in C?
...stom-generate the __start function (or whatever it is called), or at least select one from several pre-compiled alternatives. Information could be stored in the object file about which of the supported forms of main is being used. The linker can look at this info, and select the correct version of ...
What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
...var command = connection.CreateCommand()) {
command.CommandText = "SELECT MyColumn1, MyColumn2 FROM MyTable";
using (var reader = command.ExecuteReader()) {
while (reader.Read()) {
ProcessData(reader.GetString(2)); // Throws!
}
}
}...
How to join (merge) data frames (inner, outer, left, right)
...s these operations in SQL.
library(sqldf)
## inner join
df3 <- sqldf("SELECT CustomerId, Product, State
FROM df1
JOIN df2 USING(CustomerID)")
## left join (substitute 'right' for right join)
df4 <- sqldf("SELECT CustomerId, Product, State
FROM df1...