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How to import CSV file data into a PostgreSQL table?
...iter '','' quote ''"'' csv ', csv_path);
iter := 1;
col_first := (select col_1 from temp_table limit 1);
-- update the column names based on the first row which has the column names
for col in execute format('select unnest(string_to_array(trim(temp_table::text, ''()''), '','')) fro...
Intelligent point label placement in R
...0,0,0, 0.75),
col.label="white")
It works by automatically selecting an alternative location from a fine grid of points. The closest points on the grid are visited first and selected if they don't overlap with any plotted points or labels. Take a look at the source code, if you're in...
Null coalescing in powershell
...ll values in the same order as the array created in Step 1.
[0] is used to select the first element of the filtered array.
Simplifying that:
Create an array of possible values, in preferred order
Exclude all null values from the array
Take the first item from the resulting array
Caveats
Unlik...
HttpSecurity, WebSecurity and AuthenticationManagerBuilder
...allows configuration of web based security at a resource level, based on a selection match - e.g. The example below restricts the URLs that start with /admin/ to users that have ADMIN role, and declares that any other URLs need to be successfully authenticated.
protected void configure(HttpSecurity...
Where does mongodb stand in the CAP theorem?
...
MongoDB selects Consistency over Availability whenever there is a Partition. What it means is that when there's a partition(P) it chooses Consistency(C) over Availability(A).
To understand this, Let's understand how MongoDB does rep...
string.ToLower() and string.ToLowerInvariant()
... cultures. A Frenchman does not write SÉLECTIONNEZ x DE books instead of SELECT X FROM books. However, in order for the above code to work, a Turkish person would need to write SELECT x FROM books WHERE Author LİKE '%Adams%' (note the dot above the capital i, almost impossible to see). This wou...
Mysql adding user for remote access
... that you have to create or update a user. look for all your mysql users:
SELECT user,password,host FROM user;
as soon as you got your user set up you should be able to connect like this:
mysql -h localhost -u gmeier -p
hope it helps
...
Why should I avoid std::enable_if in function signatures
...{}
}
Tag dispatching does not manipulate the overload set, but helps you select exactly the function you want by providing the proper arguments through a compile-time expression (e.g. in a type trait). In my experience, this is much easier to debug and get right. If you are an aspiring library wri...
How to list all properties of a PowerShell object
...
You can also use:
Get-WmiObject -Class "Win32_computersystem" | Select *
This will show the same result as Format-List * used in the other answers here.
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Increment a database field by 1
...complex depending on your specific needs:
INSERT into mytable (logins)
SELECT max(logins) + 1
FROM mytable
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