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Update or Insert (multiple rows and columns) from subquery in PostgreSQL
...table.col1 = 123;
For the INSERT
Use:
INSERT INTO table1 (col1, col2)
SELECT col1, col2
FROM othertable
You don't need the VALUES syntax if you are using a SELECT to populate the INSERT values.
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What is the best way to iterate over a dictionary?
...e wrong collection type in the first place), you should iterate dictionary.Select( (kvp, idx) => new {Index = idx, kvp.Key, kvp.Value}) instead and not use .ElementAt inside the loop.
– spender
Mar 2 '15 at 2:17
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Why do we need a fieldset tag?
... without using tables. The fieldset tag can be used to create boxes around selected elements and the legend tag will give a caption to those elements. In this way form elements can be grouped together into identified categories.
Different browsers may display the default fieldset border in differen...
Is quitting an application frowned upon?
...em.exit when the app is updated (otherwise I'll get serialization or class cast exceptions based on my code changes). I should mention though that I do not give the user a UI handle to kill the app via system.exit - it is reserved for me as the engineer of the app to be used only when the app absolu...
iTerm2 keyboard shortcut - split pane navigation
...erences -> Profiles/<Your Profile>/Keys). There you have actions "Select Split Pane Above", "Select Split Pane Below", "Above" "Down".
– Sundar
Aug 11 '18 at 19:07
ad...
Difference between CTE and SubQuery?
...
CTE's are most useful for recursion:
WITH hier(cnt) AS (
SELECT 1
UNION ALL
SELECT cnt + 1
FROM hier
WHERE cnt < @n
)
SELECT cnt
FROM hier
will return @n rows (up to 101). Useful for calendars, dummy rowsets etc.
They are als...
Cannot generate iOS App archive in xcode
...using your archive to create an archive file rather than an ipa do this:
Select the archive and click the Distribute button.
Select the 'Save Built Products' option.
Hit Next and Save.
Browse the created directory in Finder.
The 'libraries' subdirectory will identify the libraries that you nee...
How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
...
In "Elements" panel, press Ctrl+F
In the search box, type in XPath or CSS Selector, if elements are found, they will be highlighted in yellow.
Firefox (since version 75)
Since FF 75 it's possible to use raw xpath query without evaluation xpath expressions, see documentation for more info.
Fir...
Emacs bulk indent for Python
...
I use the following snippet. On tab when the selection is inactive, it indents the current line (as it normally does); when the selection is inactive, it indents the whole region to the right.
(defun my-python-tab-command (&optional _)
"If the region is active, s...
What's the difference between IQueryable and IEnumerable
...to execute the entire query against the underlying data source (like using SELECT TOP 1 in SQL).
See:
The .NET Standard Query Operators
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