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How to check for a valid Base64 encoded string
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calling base64String.Contains multiple times may result in poor performance incase of base64String being a large string.
– NucS
Jul 23 '15 at 11:46
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What is the difference between pull and clone in git?
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They're basically the same, except clone will setup additional remote tracking branches, not just master. Check out the man page:
Clones a repository into a newly created directory, creates remote-tracking branches for each branch in ...
Summarizing multiple columns with dplyr? [duplicate]
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The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
Multiple DB Contexts in the Same DB and Application in EF 6 and Code First Migrations
...lied to the target database.
Applying explicit migrations: [201402032113124_InitialDatabaseCreation].
Applying explicit migration: 201402032113124_InitialDatabaseCreation.
Running Seed method.
PM> Update-Database -ConfigurationTypeName WebApplication3.Migrations.AnotherDbContext.Configuration
Sp...
Is there a way to get the source code from an APK file?
The hard drive on my laptop just crashed and I lost all the source code for an app that I have been working on for the past two months.
All I have is the APK file that is stored in my email from when I sent it to a friend.
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How do I know which version of Javascript I'm using?
...eaten-path one is IE9 - it implements ECMAScript 5, but doesn't implement all the features of JavaScript 1.8.5 (not sure what they're calling this version of JScript, engine codenamed Chakra, yet).
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What are the drawbacks of Stackless Python? [closed]
...and it seems to have many advantages compared with vanilla cPython. It has all those cool features like infinite recursion, microthreads, continuations, etc. and at the same time is faster than cPython (around 10%, if the Python wiki is to be believed) and compatible with it (at least versions 2...
How to convert an Int to a String of a given length with leading zeros to align?
...this Q&A becomes the canonical compendium,
scala> import java.text._
import java.text._
scala> NumberFormat.getIntegerInstance.asInstanceOf[DecimalFormat]
res0: java.text.DecimalFormat = java.text.DecimalFormat@674dc
scala> .applyPattern("0000000")
scala> res0.format(123)
res2: S...
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
...d Visual Basic books talk about them to a certain extent, but they never really go into any real detail.
13 Answers
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Checking for an empty field with MySQL
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If you want to find all records that are not NULL, and either empty or have any number of spaces, this will work:
LIKE '%\ '
Make sure that there's a space after the backslash. More info here: http://dev.mysql.com/doc/refman/5.0/en/string-com...