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What does $_ mean in PowerShell?

...dItem | Add-Member -Type NoteProperty -Name Bar -Value $_.Name -PassThru | Select Bar ... Well, it can work if you have a $_ in the scope where you're executing that pipeline. But that's very different from what you usually mean when trying to write something like that. – Joey ...
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How do I ignore all files in a folder with a Git repository in Sourcetree?

... For Sourcetree users: If you want to ignore a specific folder, just select a file from this folder, right-click on it and do "Ignore...". You will have a pop-up menu where you can ignore "Ignore everything beneath: <YOUR UNWANTED FOLDER>" If you have the "Ignore" option greyed out...
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How can I return pivot table output in MySQL?

...OUP BY. The basic SQL providing this pivot can look something like this: SELECT P.`company_name`, COUNT( CASE WHEN P.`action`='EMAIL' THEN 1 ELSE NULL END ) AS 'EMAIL', COUNT( CASE WHEN P.`action`='PRINT' AND...
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How to use greater than operator with date?

..._date with single quote causing it to become string, use backtick instead SELECT * FROM `la_schedule` WHERE `start_date` > '2012-11-18'; SQLFiddle Demo share | improve this answer |...
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly

... 0.0 NaN 0.0 3 0.0 1.0 2.0 3.0 4 NaN 0.0 NaN NaN If you want to select the rows that have two or more columns with null value, you run the following: >>> qty_of_nuls = 2 >>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index] 0 1 2 3 1 0.0 NaN 0...
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Python pandas Filtering out nan from a data selection of a column of strings

... }, onDemand: true, discardSelector: ".discard-answer" ,immediatelyShowMarkdownHelp:true,enableSnippets:true }); } }); ...
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Best way to organize jQuery/JavaScript code (2013) [closed]

... var parent = ""; if(selected_folder != "" ){ parent = selected_folder+" .content"; } $R.find(".layer").clone() .addClass(name).html(...
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Execute raw SQL using Doctrine 2

...public function getAuthoritativeSportsRecords() { $sql = " SELECT name, event_type, sport_type, level FROM vnn_sport "; $em = $this->getDoctrine()->getManager(); $stmt = $em->getConnection()->prepare($sql...
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How to select the row with the maximum value in each group

In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset: ...
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Checkbox for nullable boolean

...ents your null, whatever the semantics of null means. You could use a <select><option> drop down list to save real estate, but the user has to click twice and the choices aren't nearly as instantaneously clear. 1 0 null True False Not Set Yes No Undecided Male Fema...