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Unable to cast object of type 'System.DBNull' to type 'System.String`
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You're right, I started to optimize the condition check part, haven't looked at the line before. Mea culpa.
– User
May 15 '09 at 20:28
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Fragments onResume from back stack
...other fragments in the layout as necessary.
Edit:
The fragment has an onStart(...) which is invoked when the fragment is visible to the user. Similarly an onResume(...) when visible and actively running. These are tied to their activity counterparts.
In short: use onResume()
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How to download a branch with git?
...anch in local-branch-name.
You could switch to that local-branch-name and start work:
git checkout [local-branch-name]
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How do I format a number with commas in T-SQL?
...rse I am getting all sorts of large numbers in the results and my eyes are starting to gloss over. It would be really convenient if I could format all those numbers with commas (987654321 becomes 987,654,321). Funny that in all the many years I've used SQL Server, this issue has never come up sinc...
What is the “continue” keyword and how does it work in Java?
...resort, and then to make sure their use is grouped together tightly at the start or end of the loop so that the next developer can see the "bounds" of the loop in one screen.
continue, break, and return (other than the One True Return at the end of your method) all fall into the general category o...
Best way to build a Plugin system with Java
... OSGi practices to do exactly what the OP wants. In swing too, not SWT. Webstarted as well. good starting resource: neilbartlett.name/blog
– basszero
Jan 21 '09 at 14:42
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Show constraints on tables command
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Beware that MariaDB starting with 10.2 will return awkward results here. jira.mariadb.org/browse/MDEV-15377
– stamster
Feb 24 '18 at 18:14
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try {} without catch {} possible in JavaScript?
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It's possible to have an empty catch block, without an error variable, starting with ES2019. This is called optional catch binding and was implemented in V8 v6.6, released in June 2018. The feature has been available since Node 10, Chrome 66, Firefox 58, Opera 53 and Safari 11.1.
The syntax is ...
Set environment variables from file of key/value pairs
...e tested this with bash 3.2.51(1)-release
Update:
To ignore lines that start with #, use this (thanks to Pete's comment):
export $(grep -v '^#' .env | xargs)
And if you want to unset all of the variables defined in the file, use this:
unset $(grep -v '^#' .env | sed -E 's/(.*)=.*/\1/' | xarg...
Paste multiple columns together
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# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three co...