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How to find the size of an array in postgresql
...ikely) and are running PostgreSQL 9.4 or higher, you can use cardinality:
SELECT cardinality(id) FROM example;
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:after vs. ::after
...nal difference between the CSS 2.1 :after and the CSS 3 ::after pseudo-selectors (other than ::after not being supported in older browsers)? Is there any practical reason to use the newer specification?
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How to replace four spaces with a tab in Sublime Text 2?
...er), ensure it says Tab Width: 4 for converting from four spaces, and then select Convert Indentation to Tabs from the contextual menu that will appear from the initial click.
Similarly, if you want to do the opposite, click the Spaces or Tab Width text on the status bar and select from the same me...
How do I display a text file content in CMD?
...e lines in the text file simply read the file using Get-Content, then have Select-Object pick out the last five items/lines for you:
Get-Content c:\scripts\test.txt | Select-Object -last 5
Source: Using the Get-Content Cmdlet
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How to customize ?
...ated via the label.
If you want to display the user’s chosen path after selection, you can listen for the change event with JavaScript and then read the path that the browser makes available to you (for security reasons it can lie to you about the exact path). A way to make it pretty for the end ...
How to delete an old/unused Data Model Version in Xcode
... model version were re-sorted improperly and the wrong default version was selected as I re-added the xcdatamodel file into the project. This may be because I am up to 38 model versions and I haven't changed the default version name, so the versions are named "MY_APP 37.xcdatamodel". I wanted to del...
Chrome: console.log, console.debug are not working
... of today, the UI of developer tools in Google chrome has changed where we select the log level of log statements being shown in the console. There is a logging level drop down beside "Filter" text box. Supported values are Verbose, Info, Warnings and Errors with Info being the default selection.
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Remove duplicates in the list using linq
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var distinctItems = items.GroupBy(x => x.Id).Select(y => y.First());
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The Definitive C Book Guide and List
...02). Very good introductory stuff.
Applications Programming in ANSI C - Richard Johnsonbaugh and Martin Kalin (1996).
Intermediate
Modern C — Jens Gustedt (2017 1st Edn; 2020 2nd Edn). Covers C in 5 levels (encounter, acquaintance, cognition, experience, ambition) from beginning C to advanced...
jQuery: checking if the value of a field is null (empty)
... be null, it's always a string value. this isn't entirely true. I've got a select containing no options. When I perform .val() on this it returns null. Jquery 1.7.2
– Liam
Jan 14 '13 at 11:07
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