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What's the opposite of head? I want all but the first N lines of a file
...first 2 lines, -n +3 should give you the output you are looking for (start from 3rd).
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MySQL error: key specification without a key length
...d, and the trick is to choose a number N that’s long enough to give good selectivity, but short enough to save space. The prefix should be long enough to make the index nearly as useful as it would be if you’d indexed the whole column.
Before we go further let us define some important terms. In...
Warning as error - How to rid these
...h of your projects and change that setting:
Right-click on your project, select "Properties".
Click "Build".
Switch "Treat warnings as errors" from "All" to "Specific warnings" or "None".
The location of this switch varies, depending on the type of project (class library vs. web application, for...
What's the fastest way to do a bulk insert into Postgres?
...200, 300]),
UNNEST(ARRAY['a', 'b', 'c'])
);
without VALUES using subselect with additional existance check:
INSERT INTO tablename (fieldname1, fieldname2, fieldname3)
SELECT * FROM (
SELECT UNNEST(ARRAY[1, 2, 3]),
UNNEST(ARRAY[100, 200, 300]),
UNNEST(ARRAY['a', 'b...
PHP MySQL Google Chart JSON - Complete Example
... else
{
//echo ("Connect Successfully");
}
$query = "SELECT Date_time, Tempout FROM alarm_value"; // select column
$aresult = $con->query($query);
?>
<!DOCTYPE html>
<html>
<head>
<title>Massive Electronics</title>
<script ty...
In a storyboard, how do I make a custom cell for use with multiple controllers?
... = [controller.tableView indexPathForCell:self];
[controller.tableView selectRowAtIndexPath:path animated:NO scrollPosition:UITableViewScrollPositionNone];
[controller performSegueWithIdentifier:@"FinishedTask" sender:controller];
[super touchesEnded:touches withEvent:event];
}
@end
I...
SQL Logic Operator Precedence: And and Or
...te:
Declare @x tinyInt = 1
Declare @y tinyInt = 0
Declare @z tinyInt = 0
Select Case When @x=1 OR @y=1 And @z=1 Then 'T' Else 'F' End -- outputs T
Select Case When (@x=1 OR @y=1) And @z=1 Then 'T' Else 'F' End -- outputs F
For those who like to consult references (in alphabetic order):
Microso...
How to set conditional breakpoints in Visual Studio?
...t a breakpoint.
Right-Click over the breakpoint, and in the popup menu you select an option that suites you.
These options are as follows:
You can set a condition, based on a code expression that you supply (select Condition from the popup menu). For instance, you can specify that foo == 8 or s...
Select distinct values from a table field
...tart with the fields in
distinct(), in the same order.
For example, SELECT DISTINCT ON (a) gives you the first row for each
value in column a. If you don’t specify an order, you’ll get some
arbitrary row.
If you want to e-g- extract a list of cities that you know shops in , the exam...
Is it possible to have a multi-line comments in R? [duplicate]
I found this old thread (from over a year ago), which explains how come R doesn't support a multi-line comments (like /* comment */ of PHP, for example).
...