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JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
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How to display default text “--Select Team --” in combo box on pageload in WPF?
...ComboBox Name="MyComboBox"
IsEditable="True"
IsReadOnly="True"
Text="-- Select Team --" />
You'll obviously need to add your other options, but this is probably the simplest way to do it.
There is however one downside to this method which is while the text inside your combo box will not be ...
Checking oracle sid and database name
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I presume SELECT user FROM dual; should give you the current user
and SELECT sys_context('userenv','instance_name') FROM dual; the name of the instance
I believe you can get SID as SELECT sys_context('USERENV', 'SID') FROM DUAL;
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Check if value exists in Postgres array
...
Simpler with the ANY construct:
SELECT value_variable = ANY ('{1,2,3}'::int[])
The right operand of ANY (between parentheses) can either be a set (result of a subquery, for instance) or an array. There are several ways to use it:
SQLAlchemy: how to filt...
Select 50 items from list at random to write to file
... leaving the original population unchanged. The resulting list is
in selection order so that all sub-slices will also be valid random
samples. This allows raffle winners (the sample) to be partitioned
into grand prize and second place winners (the subslices).
Members of the popul...
How can I select rows with most recent timestamp for each key value?
...r data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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How to get the top 10 values in postgresql?
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For this you can use limit
select *
from scores
order by score desc
limit 10
If performance is important (when is it not ;-) look for an index on score.
Starting with version 8.4, you can also use the standard (SQL:2008) fetch first
select *
from...
Resize svg when window is resized in d3.js
...u don't have to worry about sizes any more.
Here is how I did it:
d3.select("div#chartId")
.append("div")
// Container class to make it responsive.
.classed("svg-container", true)
.append("svg")
// Responsive SVG needs these 2 attributes and no width and height attr.
....
How does MySQL process ORDER BY and LIMIT in a query?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ...
getting the ng-object selected with ng-change
Given the following select element
10 Answers
10
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